Etea Mdcat 2016 — Solved Past Paper with Answers

Q1. Choose the correct sentence.

• A. Does your tram leaw before eight o'clock?
• B. Does your train leave before eight clock?
• C. Does your train leave before eight o'clock?✓
• D. Do your train leave before eight o'clock?

Explanation: In this corrected sentence: "Does" is the correct auxiliary verb used with a singular subject to form a question in the present tense. "your" is the possessive pronoun, indicating that the train belongs to the person being addressed. "train" is the noun representing the mode of transportation. "leave" is the main verb, representing the action of the train departing or starting its journey. "before eight o'clock" is a prepositional phrase indicating the time when the action (leaving) is happening. With the "Does" correction, the sentence now asks whether the person's train departs or starts its journey before 8 o'clock. It is grammatically correct and properly formed.

Q2. _ my mind, what we need in this company is a better marketing plan.

• A. For
• B. In
• C. To✓
• D. At

Explanation: “To my mind” indicates a person’s opinion or suggestion hence C is the correct option.

Q3. Your friend proved more sympathetic than I, expected he _ do.

• A. Will
• B. Shall
• C. Would✓
• D. Should

Explanation: “Would” is used to express habits or contingency (a future event that is possible but can’t be predicted with certainty.) and since the speaker “expected” he was actually trying to estimate or predict, hence C is the correct answer.

Q4. "I am disappointed that you feel you have to lie to me, Jason," said his father. Select the correct indirect speech:

• A. His father said to Jason that he is sorry to feel disappointed that he has to lie to me.
• B. Jason‘s father said to him that he was sorry that he felt he had to lie to me.
• C. Jason‘s father said that he was disappointed to know that he felt he had to lie to him.✓
• D. Jason‘s father was disappointed and sorry that he had to lie to him and that he felt it.

Explanation: The correct indirect speech is (c) Jason‘s father said that he was disappointed to know that he felt he had to lie to him. The direct speech is "I am disappointed that you feel you have to lie to me, Jason," said his father. The reporting verb is "said" and it is in the past tense. Therefore, the indirect speech tenses will also be in the past tense. The word "that" is used to introduce the reported speech. The reported speech is "he felt he had to lie to him." The pronoun "he" refers to Jason, and the pronoun "him" refers to Jason's father. The verb "feel" is changed to the past tense "felt" because the reporting verb is in the past tense. The verb "lie" is also changed to the past tense "lied" because it is part of the reported speech. The indirect speech is therefore "Jason‘s father said that he was disappointed to know that he felt he had to lie to him."

Q5. Choose the word most similar in meaning to the capitalized word "OBLITERATE":

• A. Offend
• B. Haul
• C. Rent
• D. Destroy✓

Explanation: Obliterate means to destroy or eliminate. Hence the correct answer is D.

Q6. The revolution in art has not lost its steam; it _ on as fiercely as ever.

• A. Trudges
• B. Meanders
• C. Ambles
• D. Rages✓

Explanation: Rage may indicate uncontrollable anger, intense passion, or to continue with great force or intensity. The above sentence shows that as we move forward there come abrupt changes in the art of expression according to the given time and it goes on and keeps changing even now hence the best possible answer is D.

Q7. The principal has forbidden smoking on the campus.Select the correct passive voice:

• A. Smoking has been forbidden on the campus by the principal.✓
• B. Smoking had been forbidden on the campus by the principal.
• C. Smoking was being forbidden on the campus by the principal.
• D. It is forbidden by the principal to smoke on campus.

Explanation: When active voice is converted into passive voice the place of subject and object are interchanged in the sentence and there is no change in the tense however 3rd form of the verb is used in the passive voice. Hence the best possible answer is A.

Q8. Choose the word opposite in meaning to the capitalized word "TANGIBLE":

• A. Embodied
• B. Conceptual✓
• C. Phenomenal
• D. Verifiable

Explanation: Conceptual is something theoretical or imaginary hence B is the correct answer because it can’t be felt by touch.

Q9. Together the old man and the young boy washed the dishes. Select the correct passive voice:

• A. The old man and the young boy were washing the dishes together.
• B. The old man and the young boy together washed the dishes.
• C. The dishes were washed by the old man and the young boy together .✓
• D. Together the old man and the young boy washed thTogether, the old man and the young boy wash the dishes.

Explanation: In the original sentence, "Together the old man and the young boy washed the dishes," the subject (the old man and the young boy) is performing the action of washing the dishes. In the passive voice, the focus of the sentence shifts from the doer of the action to the receiver of the action. The passive voice sentence "The dishes were washed by the old man and the young boy together" rearranges the sentence to place the dishes (the receiver of the action) at the beginning of the sentence and emphasizes what happened to the dishes rather than who performed the action. The original sentence's structure is changed to fit the passive voice construction. In this passive voice sentence: "The dishes" is the subject of the sentence, receiving the action. "were washed" is the passive voice form of the verb "wash." "by the old man and the young boy together" indicates who performed the action (washing the dishes) without being the main focus of the sentence. This passive voice construction helps highlight the action performed on the dishes rather than who did it, which can be useful for different stylistic or communicative purposes.

Q10. Communication technology has brought a tremendous revolution in modern societies. Select the correct passive voice:

• A. A tremendous revolution has been brought by communication technology in modern societies.✓
• B. In modern societies a tremendous revolutions has been brought in communication technology.
• C. A tremendous revolution has brought in communication technology in modern societies
• D. Communication technology has tremendous revolution brought in modern societies

Explanation: Original sentence: "Communication technology has brought a tremendous revolution in modern societies." In this sentence, the subject ("Communication technology") is performing the action ("has brought") on the object ("a tremendous revolution"). To transform this into passive voice, we need to make the object of the action (the revolution) the subject of the sentence and restructure the sentence accordingly. Option (a): "A tremendous revolution has been brought in communication technology in modern societies." In this passive voice construction: "A tremendous revolution" is the subject of the sentence, which is now receiving the action. "has been brought" is the passive voice form of the verb "brought." "in communication technology in modern societies" clarifies where the revolution has been brought. In summary, option (a) is the correct passive voice transformation of the original sentence, effectively shifting the focus from the technology as the doer of the action to the revolution as the receiver of the action.

Q11. I insist _ the withdrawal of your statement.

• A. For
• B. On✓
• C. At
• D. In

Explanation: Insist "on” is an idiom to show that one believes that something is necessary or important. Hence the best possible answer is B.

Q12. As you have not prepared your work, ……

• A. You may not fail in the examination
• B. You could prepare harder next time
• C. You would do better in the examination
• D. You are not likely to do well this time✓

Explanation: The statement "As you have not prepared your work" indicates that the person mentioned has not adequately prepared for something. The appropriate completion of the sentence should convey a potential outcome based on their lack of preparation. Option (d) "You are not likely to do well this time" is the correct choice because it reflects the consequence of not being prepared. It suggests that due to the lack of preparation, the person's performance is expected to be negatively impacted.

Q13. Choose the word opposite in meaning to the capitalized word "ANARCHIC":

• A. Riotous
• B. Turbulent
• C. Disordered
• D. Organized✓

Explanation: Something is “organized” when it is arranged efficiently. Hence the correct answer is D.

Q14. "Frown on somebody" means to:

• A. Fall flat upon a stranger
• B. Stay alive working hard
• C. Unable to be successful
• D. Disapprove of somebody✓

Explanation: Frown on” is a phrasal verb (A phrasal verb combines two or more words to describe a specific action. Phrasal verbs can be difficult to get right, as their meaning usually has nothing to do with the definition of the component words.) which means to “disapprove of something or somebody. Hence the correct answer is D.

Q15. Choose the word most similar in meaning to the capitalized word "PRODIGIOUS".

• A. Enormous✓
• B. Sacred
• C. Seismic
• D. Tiny

Explanation: “Prodigious” is an adjective for something great in size or degree (enormous). Hence the best possible answer is A.

Q16. If you like sport, this is a great place. There‘s a lot to choose _.

• A. Among
• B. From✓
• C. At
• D. For

Explanation: When you say “choose from” it gives you the liberty to choose more than one item. Hence the best possible answer is B.

Q17. The candidate _ when asked why he had left his last job; he did not want to admit that he had been dismissed.

• A. Demurred
• B. Confided
• C. Dissembled✓
• D. Rejoiced

Explanation: Dissemble” means to conceal your true feeling or intentions. Hence the best possible answer is C.

Q18. Choose the correct sentence:

• A. However, it didn't take long for others to jump on board.✓
• B. However it didn't take long for others to jump on board.
• C. However, it didn't take long for others to jump on board?
• D. However. It didn't take long for others to jump on board.

Explanation: A 'comma' is usually added after 'however' to emphasize a pause and to indicate how different ideas are being discussed.

Q19. Anwar said, "Naveed must go tomorrow". Select the correct indirect speech:

• A. Anwar declared that Naveed must have gone the following day✓
• B. Anwar exclaimed that Naveed would have to go the following day.
• C. Anwar said that Naveed would have to go the following day.
• D. Anwar said that Naveed shall go the following day.

Explanation: Modal verbs (such as can, may, should, and will) are auxiliary verbs used to express possibility, probability, or necessity. In the simple active past, present, and future tenses, these verbs are followed by the root (bare infinitive) form of the verb. The passive construction for the simple tense is modal + form of be + past participle.

Q20. The tissues present in anglosperms but absent in gymnosperms are:

• A. Vessels
• B. Companion cell
• C. Sieve tube
• D. Both (a) and (b)✓

Explanation: The answer is both a and b. Both vessels and companion cells are present in angiosperms but absent in gymnosperms. Vessels are long, hollow tubes that transport water and dissolved minerals throughout the plant. They are absent in most gymnosperms, with the exception of Gnetum. Companion cells are small, living cells that are closely associated with sieve cells in the phloem. They help to support the sieve cells and provide them with nutrients. Companion cells are also thought to be involved in the transport of carbohydrates in the phloem. The absence of vessels and companion cells in gymnosperms is one of the key anatomical differences between these two groups of plants. This difference has implications for the way that water and carbohydrates are transported in gymnosperms, and it may also contribute to the different growth habits of these plants.

Q21. Individuality of every persons is maintained by nucleotide genome sequence difference of:

• A. 0.1%✓
• B. 2%
• C. 3%
• D. 5%

Explanation: 0.99.9% of genome sequences are the same for all humans. Humans differ from one another due to differences of 0.1% in their gene sequence.

Q22. Mature cells of cartilage are:

• A. Chondrocytes✓
• B. Osteocytes
• C. Osteoblasts
• D. Osteoclasts

Explanation: Cartilage is a form of connective tissue. The mature cells of cartilages are chondrocytes. Chondrocytes are found in lacunae, which are small spaces in the cartilage matrix. They are responsible for the production and maintenance of the cartilage matrix. Chondrocytes are also responsible for the repair of cartilage damage.

Q23. Of the following the dioecous plant be:

• A. Sun-flower
• B. Wheat
• C. Mulberry✓
• D. Maize

Explanation: Dioecious plants are those that have separate male and female individuals. This means that each plant will either produce male flowers or female flowers, but not both. Mulberry is an example of a dioecious plant, with male and female trees that are easily distinguished by their flowers.

Q24. Each kidney of human being is weighing about:

• A. 140 grams
• B. 160 grams✓
• C. 130 grams
• D. 150 grams

Explanation: The weight of each human kidney is about 160 grams.

Q25. Which one of the following discovered the vaccine for first time against the small pox in 1796.

• A. Edward Jenner✓
• B. Hoistem wings
• C. F. H Herbor
• D. Jammes Shwang

Explanation: In 1796, Edward Jenner first vaccinated an 8 years old boy with material removed from cowpox lesions on the hand of a milkmaid. After six weeks the boy was inoculated with pus from a smallpox victim, but he did not develop the disease.

Q26. The main axis culminates in a flower and produces three or more daughter axis each of which continues the branching in similar manner is know as:

• A. Uniparous cyme
• B. Biparous cyme
• C. Multiparous cyme✓
• D. Cymose capitulum

Explanation: The main axis culminates in a flower and produces three or more daughter axis each of which continues the branching in similar manner is known as multiparous cyme. A multiparous cyme is a type of cymose inflorescence in which the main axis terminates in a flower, and then produces three or more daughter axes, each of which continues to branch in a similar manner. This type of inflorescence is often seen in plants such as snapdragons, carnations, and poinsettias.

Q27. The ripened & fertilized ovule is called:

• A. Fruit
• B. Seed✓
• C. Endosperm
• D. Perisperm

Explanation: The ripened and fertilized ovule is called a seed. A seed is a ripened ovule, which has three functions: To protect the embryo. To provide nutrients for the embryo. To disperse the embryo to a new location. The seed coat is the outermost layer of the seed. It protects the embryo from damage and helps to regulate the exchange of gases. The endosperm is the tissue that provides nutrients for the embryo. It is usually made up of starch, but it can also contain other nutrients, such as proteins and oils. The embryo is the developing plant. It is contained within the endosperm and is protected by the seed coat.

Q28. Which one of the following comes into existence when bacterial plasmid naturally modified to produce it?

• A. pBR 322✓
• B. Npq 303
• C. oSR 210
• D. kMG 319

Explanation: One common type of vector is a plasmid. Plasmids were discovered by investigators studying the sex life of the intestinal bacterium Escherichia coli. Plasmids are natural extrachromosomal circular DNA molecules which carry genes for antibiotic resistance and fertility etc. One of the plasmids discovered earlier, pSC 101 has antibiotic resistance genes for tetracycline, whereas pBR 322 has antibiotic resistance genes for tetracycline as well as ampicillin.

Q29. Exophthalmia is a classic symptom of:

• A. Hyperthyroidism✓
• B. Hypocalcemia
• C. Hypochondria
• D. Hypercalcemia

Explanation: Exophthalmia is a classic symptom of Graves' disease, which is a type of hyperthyroidism. Hyperthyroidism is a condition in which the thyroid gland produces too much of the hormone thyroxine. Thyroxine is a hormone that helps to regulate metabolism, and when it is produced in excess, it can cause a number of symptoms, including exophthalmia. Exophthalmia is the protrusion of the eyeballs. It is caused by an increase in the amount of tissue around the eyes, including the muscles, fat, and connective tissue. This increase in tissue can be caused by a number of factors, including Graves' disease, an infection, or an injury.

Q30. Percentage of CO2 carried by plasma proteins is:

• A. 5%
• B. 6%
• C. 7%✓
• D. 8%

Explanation: Carbon dioxide is transported in the blood in several different states. Some of the carbon dioxide (about 20%) is carried as carboxyhemoglobin. Carboxyhaemoglobin is formed when carbon dioxide combines with an amino group of hemoglobin. Other plasma proteins also carry about 7% carbon dioxide. About 70% carbon dioxide is carried as bicarbonate ion combined with sodium in the plasma.

Q31. "C.S.F" is found in between.

• A. Pia matter and dura mater
• B. Pia mater and arachnoid mater✓
• C. Pia mater and neural canal
• D. Dura mater and arachnoid mater

Explanation: Cerebrospinal fluid (CSF) is found between the pia mater and arachnoid mater. The pia mater is the innermost layer of the meninges, which are the membranes that surround the brain and spinal cord. The arachnoid mater is the middle layer of the meninges. The space between the pia mater and arachnoid mater is called the subarachnoid space. The subarachnoid space is filled with CSF, which helps to cushion the brain and spinal cord from injury.

Q32. Kelps are:

• A. Diatoms
• B. Red-algae
• C. Green-algae
• D. Brown-algae✓

Explanation: Kelps are brown algae. They are the largest and most complex of all algae, and they can grow up to 200 feet long. Kelps are found in cold, nutrient-rich waters, and they play an important role in the marine ecosystem. They provide food and shelter for a variety of marine animals, and they also help to filter the water.

Q33. Independent gametophyte and sporophyte are found in:

• A. Selaginella
• B. Polytrichum
• C. Ectocarpus✓
• D. Liverworts

Explanation: Ectocarpus is a genus of brown algae, and it exhibits an alternation of generations life cycle, which involves both gametophytic and sporophytic phases. In the case of Ectocarpus, the life cycle includes an independent gametophyte and a sporophyte phase.

Q34. The guard cell of the stomata in Monocot is:

• A. Kidney shape
• B. Oval
• C. Rounded
• D. Dumbbell shaped✓

Explanation: Dicots possess a stomatal complex with a pair of kidney-shaped guard cells, while those of monocots The guard cells of the stomata in Monocot are dumbbell-shaped. They are elongated and tapered at both ends, giving them a dumbbell-like appearance. This shape is characteristic of monocot plants, and is different from the bean-shaped guard cells found in dicot plants. The dumbbell-shaped guard cells of monocots are thought to be better suited for regulating gas exchange in these plants. The dumbbell shape allows the guard cells to expand and contract more easily, which helps to control the size of the stomatal aperture. This is important for monocots, as they often grow in hot and dry environments where it is important to conserve water. consist of dumbbell-shaped guard cells with adjacently arranged subsidiary cells. The dumbbell-shaped guard cells of monocots are thought to be better suited for regulating gas exchange in these plants. The dumbbell shape allows the guard cells to expand and contract more easily, which helps to control the size of the stomatal aperture. This is important for monocots, as they often grow in hot and dry environments where it is important to conserve water. consist of dumbbell-shaped guard cells with adjacently arranged subsidiary cells.

Q35. Photorespiration involved the following reaction which occurs in the sequence of:

• A. Glycolate --> Glycine, Glycine --> Serine + CO2, RuBP + O2 --> Glycolate
• B. RuBP+ O2 --> Glycolate, Glycine --> Serine+ CO2, Glycolate --> Glycine
• C. RuBP+ O2 --> Glycolate, Glycolate --> Glycine, Glycine --> Serine + CO2✓
• D. Glycine --> Serine + CO2, RuBP+ O2 --> Glycolate, Glycolate --> Glycine

Explanation: Following are the steps involved in photorespiration;RuBP + O2 to 8 GlycolateGlyoxylate to glycine2 glycine to serine + CO2 The right option is C.

Q36. Which of the following statement is correct?

• A. Inspiration is an active process✓
• B. Expiration is an active process
• C. Inspiration is a passive process
• D. Both expiration and inspiration are passive processes

Explanation: Inspiration occurs via active contraction of muscles so, is an active process.

Q37. Porifera is related to the sub Kingdom of:

• A. Protozoa
• B. Parazoa✓
• C. Metazoa
• D. Aves

Explanation: Porifera is related to the subkingdom Parazoa. Parazoa is a subkingdom of the kingdom Animalia that includes sponges. Sponges are the simplest multicellular animals, and they do not have a true tissue organization. They are filter feeders, and they obtain their food by drawing water through their bodies and filtering out small particles.

Q38. The females of one of the following classes possess a single overy, that is:

• A. Pisces
• B. Amphibia
• C. Reptilia
• D. Aves✓

Explanation: The answer is Aves. Females of the class Aves (birds) have a single ovary, located on the left side of their body. The right ovary is. Females of the class Aves (birds) have a single ovary, located on the left side of their body. The right ovary is present in the embryo, but it regresses during development and is non-functional in the adult bird. This is thought to be an adaptation for flight, as it reduces the weight of the bird's body.rd. This is thought to be an adaptation for flight, as it reduces the weight of the bird's body.

Q39. The florescent pigments in the eyes of fruit fly is an example of:

• A. Over dominance
• B. Complete dominance
• C. Incomplete dominance✓
• D. Co-dominance

Explanation: The florescent pigments in the eyes of fruit flies is an example of incomplete dominance. This means that the two alleles for eye color, red and brown, are not completely dominant or recessive, but instead blend together to produce a third color, sepia.

Q40. The roots given out from rhizome of fern are called:

• A. Pneumatophore
• B. Phizophores
• C. Rhizoids
• D. Adventitious roots✓

Explanation: The roots given out from the rhizome of a fern are called "adventitious roots." Adventitious roots are roots that arise from plant parts other than the primary root system, which includes roots that emerge from stems, leaves, or, in the case of ferns, rhizomes. In ferns, the rhizome is a horizontal, underground stem that gives rise to both roots and fronds (the leaves of ferns). The adventitious roots help anchor the fern to the substrate and absorb water and nutrients from the soil. These roots are an essential part of the fern's overall structure and contribute to its ability to thrive in various environments.

Q41. Pigment combination of a carotenoid is:

• A. Blue, green, brown, or red
• B. Orange, yellow, blue, or brown
• C. Yellow, orange, red, or brown✓
• D. Blue, red, orange, or brown

Explanation: Accessory photosynthetic pigments present in the chloroplasts include yellow and red to orange carotenoids; carotenes are mostly red to orange and xanthophylls are yellow to orange/brown. These broaden the absorption and utilization of light energy.

Q42. The study of fishes is called:

• A. Ornithology
• B. Ichthyology✓
• C. Herpetology
• D. Ethology

Explanation: The study of fishes is called ichthyology. It is a branch of zoology that deals with the scientific study of fish. Ichthyologists study the morphology, anatomy, physiology, behavior, ecology, and evolution of fish. They also study the taxonomy and classification of fish.

Q43. D.N.A of bacterium is:

• A. Haploid, single stranded, coiled
• B. Diploid, double stranded, coiled
• C. Haploid, double stranded, coiled✓
• D. Diploid, single stranded, coiled

Explanation: The nuclear material or DNA in bacterial cells occupies a position near to the center of the cell. This material is a single, circular and double stranded DNA molecule. This chromatin body is actually an extremely long molecule of DNA that is tightly folded [coiled] so as to it inside the cell component. Since bacteria have a single chromosome, they are haploid.

Q44. Chiroptera are:

• A. Flying mammals✓
• B. Flesh eating mammals
• C. Hoofed mammals
• D. Aquatic mammals

Explanation: Chiroptera are flying mammals. They are the only mammals that are capable of true flight. Their wings are formed by a membrane of skin that stretches between their elongated fingers and body. Bats are found all over the world, except for the polar regions and some isolated oceanic islands.

Q45. The swallowing process is regulated by:

• A. Throat
• B. Pharynx
• C. Medulla oblongata✓
• D. Stomach

Explanation: The swallowing process is regulated by pharynx. The slimy food mass is rolled into a small oval lump called bolus, which is then pushed to the back of the mouth by the action of tongue and muscles of pharynx which ensure that the food does not enter the windpipe.

Q46. World-wide, mortality rate per annum due to AIDS is more than:

• A. One million
• B. Two million
• C. Three million✓
• D. five-million

Explanation: It is a fact. AIDS is a contagious disease which is common worldwide. Sexual contact is one of the major sources of its spread. The treatment for AIDS is not available at present.

Q47. "Portuguese-man of war" is the:

• A. Desert-snake
• B. Coelenterate✓
• C. A big-reptile
• D. Black-forest monkey

Explanation: The Portuguese-man-of-war is a coelentrate. Coelenterates are a phylum of marine invertebrates that includes jellyfish, sea anemones, and hydras. The Portuguese-man-of-war is not a snake, a reptile, or a monkey. It is a colonial organism made up of many individual polyps that work together as a single unit. The polyps are specialized for different tasks, such as floating, capturing prey, and reproduction. The Portuguese-man-of-war is a venomous creature that can deliver a painful sting to humans.

Q48. Rootless, stem-less and leafless plants are:

• A. Liverworts✓
• B. Mosses
• C. Psilopsida
• D. Onion

Explanation: The correct answer is (a) Liverworts. Liverworts are the simplest non-vascular plants. They are rootless, stem-less and leafless. They are attached to the ground by rhizoids. They reproduce by spores.

Q49. Amphibians generally have three chambers in their hearts. What type of chambers they are?

• A. One ventricle, one atrium, one outflow tract✓
• B. Two ventricles, one atrium
• C. One ventricle, one atrium
• D. One ventricle, one atrium, one sinus venous

Explanation: Bird and mammal hearts have four chambers (two atria and two ventricles). A frog, which is an amphibian, has a heart with three chambers (one ventricle and two atria), and fish hearts have two chambers (one atrium and one ventricle). Like moss, liverworts grow in moist habitats. However, they don't have leaves, stems, or roots.

Q50. Release of calcium from bone in to blood is controlled by:

• A. Parathormone✓
• B. Calcitonin
• C. Thyroxine
• D. Both (a) & (b)

Explanation: The release of calcium from bone into the blood is controlled by parathyroid hormone (PTH). PTH is a hormone that is produced by the parathyroid glands. When blood calcium levels are low, the parathyroid glands release PTH, which signals cells in bone (osteoclasts) to release calcium from the bone surfaces. PTH also signals the kidney to reclaim more calcium before it is excreted in the urine and also stimulates synthesis of the active form of vitamin D.

Q51. That 1st field trial of genetically engineered plants occurred in France and USA in:

• A. 1980
• B. 1982
• C. 1984
• D. 1986✓

Explanation: The first field trials of genetically engineered plants occurred in France and the USA in 1986. Tobacco plants were engineered to be resistant to herbicides. The first genetically modified organism (GMO) to be released into the environment was the ice-minus strain of Pseudomonas syringae in 1987. This strain of bacteria was engineered to be unable to produce ice crystals, which could have protected crops from frost damage. However, the field tests were delayed for four years due to legal challenges from environmental groups. The first commercialization of transgenic plants occurred in China in 1992, with the introduction of a virus-resistant tobacco. In 1994, the first genetically modified food, the Flavr Savr tomato, was approved for commercial release in the United States. The Flavr Savr tomato was engineered to have a longer shelf life. Genetically engineered crops are now grown in more than 20 countries around the world. The most common genetically engineered crops are soybeans, corn, cotton, and canola. These crops are engineered for a variety of traits, including herbicide resistance, insect resistance, and drought tolerance.

Q52. Sense of taste is called:

• A. Gustation✓
• B. Tactician
• C. Nociception
• D. Olfaction

Explanation: Taste perception or gustation is the sensory detection of food on the tongue.

Q53. Basidiocarps are developed by:

• A. Primary mycelium
• B. Secondary mycelium✓
• C. Tertiary mycelium
• D. Quaternary mycelium

Explanation: Basidiocarps are developed by secondary mycelium. The secondary mycelium is a mass of hyphae that forms after the primary mycelium has colonized a substrate. The secondary mycelium is responsible for the production of basidia, which are the reproductive structures of mushrooms.

Q54. Outer wall of guard cell is:

• A. Thick & elastic
• B. Thick & non elastic
• C. Thin & elastic✓
• D. Thin & non elastic

Explanation: The outer structure of the guard cell is composed of polysaccharide-based wall polymers that are extremely strong and elastic. The inner side of the guard cell is thick and elastic and the outer cell wall is comparatively thin.

Q55. Eating of high carbohydrate food are signs and symptoms of:

• A. Obesity
• B. Bulimia nervosa✓
• C. Dyspepsia
• D. Anorexia nervosa

Explanation: Incomplete or imperfect digestion is called dyspepsia. This is not a disease in itself but symptomatic of other disorders or diseases. Obesity is the term employed when a person has an abnormal amount of fat on the body. If one eats too much food than body requirement, the surplus is stored as fat so becomes overweight or obese. Anorexia nervosa;This term is employed to the loss of appetite due to the fear of becoming obese. Bulimia nervosa;It is a neurotic disorder in slightly older girls. It is characterized by bouts of over-eating fattening food such as fried food or cream cakes.

Q56. In case of immunity, the first line of body defense is:

• A. Macrophages
• B. Lymphocytes
• C. Blood cells
• D. Skin✓

Explanation: The first line of body defense is the skin. It is a physical barrier that prevents pathogens from entering the body. The skin is also covered in a layer of bacteria that help to keep pathogens in check. If pathogens do manage to penetrate the skin, they will then be met by the body's second line of defense, which includes white blood cells such as macrophages and lymphocytes. These cells help to fight off infection by engulfing and destroying pathogens. So the answer is skin. The body's first line of defense is essential for preventing infection. However, if pathogens do manage to penetrate the first line of defense, the body's second and third lines of defense will be activated to fight off the infection.

Q57. Transport of organic solutes from the source of assimilation to the source of sink is:

• A. Transportation
• B. Transduction
• C. Translocation✓
• D. Transformation

Explanation: The correct term for the transport of organic solutes from the source of assimilation to the source of sink is translocation. Translocation is a process that occurs in the phloem, a vascular tissue in plants. Phloem is made up of sieve tubes, which are long, thin tubes that transport dissolved organic solutes, such as sucrose and amino acids, from the source to the sink. The movement of organic solutes in the phloem is driven by a pressure gradient. The source has a high concentration of organic solutes, while the sink has a low concentration. This creates a pressure difference that drives the movement of the solutes from the source to the sink. Translocation is a bidirectional process, meaning that the movement of organic solutes can occur in either direction. However, in most cases, the movement is from the source to the sink.

Q58. The percentage of symbolic association by Ascomycota is more than:

• A. 50%
• B. 40%✓
• C. 20%
• D. 30%

Explanation: It is a fact.

Q59. Delayed wound healing is caused by deficiency of:

• A. Zn✓
• B. Fe
• C. Co
• D. Mn

Explanation: Delayed wound healing can be caused by a deficiency of zinc (Zn). Zinc is an essential mineral that plays a crucial role in various physiological processes, including immune function, DNA synthesis, and cell division. One of its critical functions is in the wound healing process. Zinc is involved in collagen synthesis, which is essential for the formation of the extracellular matrix in tissues, including the skin. It also plays a role in cell proliferation and migration, which are necessary for tissue repair and wound closure. A deficiency of zinc can lead to impaired wound healing, as the body's ability to produce new tissue and repair damaged skin is compromised. Proper nutrition, including an adequate intake of zinc, is essential for optimal wound healing and overall health.

Q60. Which of the following statements is correct?

• A. H3PO3 is dibasic and reducing✓
• B. H3PO3 is tribasic and reducing
• C. H3PO3 is tribasic and non-reducing
• D. H3PO3 is dibasic and non-reducing

Explanation: In the structure of H3PO3, two -OH groups are present, so it is dibasic acid. In it one P-H bond is present, so it provides hydrogen and due to such hydrogen it acts as a reducing agent.

Q61. Which of the following is correct about speed of nerve impulse:

• A. Thicker the nerve fiber-less resistance to flow of current-faster the nerve impulse.✓
• B. Thicker the nerve fiber-more resistance to flow of current-slower the nerve impulse
• C. Thinner the nerve fiber-less resistance to flow of current-slower the nerve impulse
• D. None of the above

Explanation: The correct statement is Thicker the nerve fiber-less resistance to flow of current-faster the nerve impulse. The speed of a nerve impulse is determined by the resistance of the nerve fiber to the flow of current. The thicker the nerve fiber, the less resistance it has to the flow of current, and the faster the nerve impulse will travel. The reason for this is that the thicker the nerve fiber, the more myelin sheath it has. Myelin is a fatty substance that insulates the nerve fiber, which helps to reduce the resistance to the flow of current. In contrast, thinner nerve fibers have less myelin sheath, which means that they have more resistance to the flow of current. This results in slower nerve impulses. Therefore, the thicker the nerve fiber, the faster the nerve impulse will travel.

Q62. Archaea live in both extreme and moderate environments those living in extreme condition are called:

• A. Extremophile✓
• B. Methanogeus
• C. Extremophyte
• D. Extremogeus

Explanation: The term for organisms that live in extreme environments is extremophile. Extremophiles can be found in a variety of extreme environments, including hot springs, cold deserts, and radioactive waste. They have adapted to these extreme environments by developing special features, such as the ability to withstand high temperatures or high acidity. Some examples of extremophiles include: Halophiles: These archaea live in extremely salty environments, such as the Dead Sea. Thermophiles: These archaea live in extremely hot environments, such as hot springs. Psychrophiles: These archaea live in extremely cold environments, such as the Arctic and Antarctic. Alkaliphiles: These archaea live in extremely alkaline environments, such as soda lakes. Acidiphiles: These archaea live in extremely acidic environments, such as sulfuric acid lakes. Extremophiles are of interest to scientists because they can provide insights into how life can survive in extreme environments. They may also be used to develop new products, such as enzymes that can withstand harsh conditions.

Q63. In a cricket match 500 spectators are counted one by one. How many significant figures will be there in the final result?

• A. 0
• B. 1
• C. 2
• D. 3✓

Explanation: All trailing zeros after non zero and before a decimal point are counted as significant figures.

Q64. The botanical name of deadly nightshade is:

• A. Atropa belladonna✓
• B. Taxusbaccata
• C. Narcissus spp
• D. Both (a) & (b)

Explanation: The botanical name of deadly nightshade is Atropa belladonna. Taxusbaccata is the botanical name of yew, and Narcissus spp. is the botanical name for a group of daffodils. Neither of these plants are deadly nightshade. Deadly nightshade is a poisonous plant that is native to Europe, Asia, and North Africa. It is a member of the nightshade family, Solanaceae, which also includes tomatoes, potatoes, and eggplant. The berries of deadly nightshade are especially poisonous, and even a small amount can be fatal. The plant also contains other toxic compounds, such as atropine, scopolamine, and hyoscyamine. The symptoms of poisoning by deadly nightshade include dilated pupils, flushed skin, dry mouth, blurred vision, hallucinations, and seizures. In severe cases, poisoning can lead to death.

Q65. Hormone inhibin is produced by:

• A. Hypothalamus
• B. Pituitary gland
• C. Prostrate
• D. Sertoli cells✓

Explanation: The correct answer is Sertoli cells. Inhibin is a hormone that is produced by Sertoli cells in the testes. It is a member of the transforming growth factor-beta (TGF-β) superfamily of proteins. Inhibin is involved in the regulation of spermatogenesis, the process of sperm production. Inhibin is a negative feedback regulator of FSH (follicle-stimulating hormone) secretion by the anterior pituitary gland. When inhibin levels are high, FSH secretion is suppressed. This helps to ensure that the number of sperm produced is not excessive. Inhibin is also involved in the regulation of ovarian function. Inhibin levels are high in the follicular phase of the menstrual cycle, when the ovaries are producing follicles. Inhibin levels then decrease in the luteal phase, when the ovaries are producing progesterone.

Q66. All of the following are micronutrients accept:

• A. Iron
• B. Chlorine
• C. Copper
• D. Potassium✓

Explanation: The answer is potassium. Potassium is a macromineral, not a micronutrient. Micronutrients are essential nutrients that are required in small amounts by the body. They include vitamins and minerals. Macrominerals are also essential nutrients, but they are required in larger amounts than micronutrients. They include calcium, phosphorus, magnesium, sodium, potassium, chloride, and sulfur. Potassium is also an essential nutrient, but it is required in larger amounts than the other three micronutrients. Potassium is involved in many important functions in the body, including the regulation of blood pressure and the transmission of nerve signals.

Q67. Auxin travels by diffusion towards:

• A. Shoot
• B. Flowers
• C. Leaves
• D. Base of plant✓

Explanation: Auxin travels down the shoot towards the base of the plant.

Q68. Reptiles flourished in _ period.

• A. Jurassic
• B. Mesozoic
• C. Metazoic
• D. Both (a) & (b)✓

Explanation: Reptiles flourished in the Mesozoic period. The Mesozoic era is often referred to as the "Age of Reptiles" because it was a time when reptiles were dominant and diverse. This era is divided into three periods: the Triassic, Jurassic, and Cretaceous periods. The Jurassic period is a part of the Mesozoic era, and it was indeed a time of significant reptile diversity and expansion, including the rise of various groups like dinosaurs, pterosaurs, and marine reptiles. So, the correct answer is "Both (a) & (b)" because reptiles flourished in both the Mesozoic period and the Jurassic period, which is a subdivision of the Mesozoic era.

Q69. Which of the following is non-steroidal hormone?

• A. Cortisol
• B. Testosterone
• C. Insulin✓
• D. Aldosterone

Explanation: Insulin is a non-steroidal hormone. Cortisol, testosterone, and aldosterone are all steroidal hormones. Steroid hormones are made of cholesterol and are fat-soluble, which means they can pass through the cell membrane. They bind to receptors inside the cell and activate genes. Examples of steroidal hormones include cortisol, testosterone, and aldosterone. Non-steroidal hormones are made of amino acids and are water-soluble, which means they cannot pass through the cell membrane. They bind to receptors on the cell membrane and activate enzymes. Examples of non-steroidal hormones include insulin, growth hormone, and thyroid hormones. So, the answer to your question is Insulin.

Q70. Stop codons are:

• A. UAA,UAG,UGA✓
• B. UGC,UCG,AAA
• C. UUG,UCG,UCA
• D. UAA,UGC,UCA

Explanation: Stop codons are codons (triplets of nucleotides) in messenger RNA (mRNA) that signal the termination of protein synthesis. Out of 64 codons, there are three stop codons: UAA, UAG, and UGA. These codons do not code for any amino acids hence, are known as nonsense codons. When a ribosome reaches a stop codon, it releases the amino acid chain that it has been building. This signals the end of protein synthesis. Stop codons are important for ensuring that proteins are the correct length. If a protein is not the correct length, it may not be functional. REMEMBER THEM AS UGA[ u go away] UAA [ u are away] UAG [ u are gone]

Q71. The tissue culture method occur in the following sequence:

• A. Sterilization -> media preparation -> inoculation -> callus development -> plantlets
• B. Media preparation -> sterilization -> inoculation -> callus development -> plantlets
• C. Media preparation -> inoculation -> sterilization -> callus development -> plantlets✓
• D. Inoculation -> sterilization -> media preparation -> callus development -> plantlets

Explanation: 1.Media containing agar should be adequately soaked with proper agitation before heating.[MEDIA PREPARATION] 2. Microbiologists collect a small sample of microbes from a given source (we call this small sample an "inoculum") and place them into a medium that contains the nutrients needed for growth. This process is called "inoculation".[INOCULATION] 3.Three main[ STERILIZATION]processes for packaging material are in common use, either individually or in combination: irradiation, heat, and chemical treatments. 4.Callus” in the early days of plant biology referred to the massive growth of cells and accumulation of callose associated with woundiing.[CALLUS DEVELOPMENT]

Q72. A condition in which the artery is thickened and blocked by cholesterol is called;

• A. Arteriosclerosis
• B. Atherosclerosis✓
• C. Thrombosis
• D. Embolism

Explanation: The condition in which the artery is thickened and blocked by cholesterol is called atherosclerosis. Arteriosclerosis is a general term for hardening of the arteries, but atherosclerosis is a specific type of arteriosclerosis that is caused by the buildup of plaque in the arteries. Plaque is a fatty substance that builds up on the walls of the arteries. It can be made up of cholesterol, fat, calcium, and other substances. As plaque builds up, it can narrow the arteries and reduce blood flow. This can lead to a number of problems, including heart disease, stroke, and peripheral artery disease.

Q73. Oligosaccharides are involved in the formation of:

• A. Secreted proteins
• B. Blood clotting factors
• C. Anti-bodies
• D. All of the above✓

Explanation: The answer is all of the above. Oligosaccharides are involved in the formation of all three of these types of proteins. Secreted proteins are proteins that are released from cells into the extracellular environment. They often have oligosaccharides attached to them, which help them to perform their functions in the body. For example, the oligosaccharides on insulin help it to bind to its receptor cells in the liver and muscle. Blood clotting factors are proteins that are involved in the formation of blood clots. They also often have oligosaccharides attached to them, which help them to interact with each other and to form a stable clot. Antibodies are proteins that are produced by the immune system to fight off infection. They also have oligosaccharides attached to them, which help them to bind to foreign invaders and to activate the immune system. In addition to these three types of proteins, oligosaccharides are also involved in the formation of many other types of proteins, including cell surface receptors, enzymes, and hormones. They play a critical role in many important biological processes, and their study is an active area of research.

Q74. A slowly progressive disease of the brain that is characterized by the impairment of memory and eventually by disturbance in reasoning, planning, language and perception is one of the following?

• A. Alzheimer‘s disease✓
• B. Meningitis
• C. Cerebrovascular accident
• D. Malignant

Explanation: The answer is Alzheimer's disease. Alzheimer's disease is a neurodegenerative disorder that causes a progressive decline in cognitive function. The most common symptom is memory loss, but other symptoms can include difficulty with language, reasoning, and planning. As the disease progresses, people with Alzheimer's may also experience changes in personality and behavior. There is no cure for Alzheimer's disease, but there are treatments that can help to slow the progression of the disease and improve quality of life.

Q75. The most abundant lymphocytes are:

• A. C–cells
• B. A & B cells
• C. B & C cells
• D. B & T cells✓

Explanation: The most abundant lymphocytes in the human body are B and T cells. B cells and T cells are the two primary types of lymphocytes that play a crucial role in the immune system. B cells are responsible for producing antibodies, which help in identifying and neutralizing foreign invaders like bacteria and viruses. T cells have various functions, including directly attacking infected cells, coordinating the immune response, and regulating other immune cells.

Q76. The number of cortical nephrons are:

• A. 70–80%
• B. 80–90%✓
• C. 60–70%
• D. 60–80%

Explanation: Approximately 80%-90% of all nephrons in the human kidney are cortical nephrons. These nephrons have their glomeruli located in the outer cortex of the kidney and have relatively short loops of Henle that do not extend deep into the medulla. They are the most abundant type of nephrons in the kidney.

Q77. The outer tissue of cambium develops in to:

• A. Xylem
• B. Phloem✓
• C. Cortex
• D. Epidermis

Explanation: The outer tissue of cambium develops into phloem. The cambium produces phloem on its outer side, which is responsible for transporting sugars and other organic compounds throughout the plant.

Q78. The 1st symptom of Leaf curl disease of cotton infection appear within:

• A. 1 – 2 weeks
• B. 2 – 3 weeks✓
• C. 3 – 4 weeks
• D. 4 – 5 weeks

Explanation: The symptoms of leaf curl disease occur within 2 to 3 weeks.

Q79. The mutation that occurs in an egg or sperm cell, or those that occur just after fertilization, are called _ mutation.

• A. New
• B. De novo
• C. Drift
• D. Both (a) & (b)✓

Explanation: The answer is Both a & b. De Novo Mutation: It is a type of mutation that occurs in the germ cells (egg or sperm) of an organism. They can be either beneficial, neutral, or harmful. The term de novo comes from the Latin phrase "de novo" which means "from the new". This type of mutation is a new mutation that is not inherited from the parents. It can be caused by a number of factors, including environmental exposure, errors in DNA replication, and recombination.

Q80. The hydrated cations of first transition series that imparts a blue color:

• A. Cr+2, CO+2, Cu+2✓
• B. Cu+2, Zn+2, Ti+4
• C. Tt+3, Zn+2, Cu+2
• D. Cr+3, Tt+4, Cu+2

Explanation: Colored compounds of transition elements are associated with partially filled (n-1)d orbitals. The transition metal ions contain unpaired d-electrons which undergo an electronic transition from one d-orbital to another. During this d-d transition process, the electrons absorb certain energy from the radiation and emit the remainder of energy as colored light hence, the colored ion is formed due to the d-d transition which falls in the visible region for all transition elements. Therefore, the correct answer is A.

Q81. Select the correct order of the acids strength?

• A. CH3COOH>>CHCl2COOH>CH2ClCOOH
• B. CHCl2COOH>CH2ClCOOH>CH3COOH✓
• C. CH3COOH>CHCl2COOH>CH2ClCOOH
• D. CHCl2COOH>>CH2COOH>CH2ClCOOH

Explanation: The presence of groups near the -COOH group of a carboxylic acid affects acidity. Generally, electron-withdrawing groups increase acidity by increasing the stability of the carboxylate ion through delocalization of negative charge and inductive effect. The presence of electron-donating groups decreases acidity by destabilizing the carboxylate ion. Therefore the most stable and highest acidic strength is of the one having the least number of Hydrogen atoms according to which B is the most suitable answer.

Q82. Which is not correct about the manufacture of ammonia by Haber – Process? The break opening of the nitrogen triple bond (N = N) to form N2H2 in first step of the reaction is taken as:

• A. Very difficult step
• B. Highly unstable product
• C. Highly endothermic✓
• D. None of the above

Explanation: The Haber process involves a reversible reaction at dynamic equilibrium. In the Haber process the forward reaction is exothermic (1st step in the forward direction) hence the correct answer is C. It must be noted that the reverse reaction in this process is endothermic. This means that as the temperature is increased, the position of equilibrium moves to the left, and the yield of ammonia decreases.

Q83. Carbon monoxide can be converted by hydrogenolysis to alkanes by the process known as:

• A. Contact process
• B. Fischer-tropsch (FT) process✓
• C. Fermentation process
• D. Haber-Bosch process

Explanation: Hydrogenolysis is a catalytic chemical reaction that breaks a chemical bond in an organic molecule with the simultaneous addition of a hydrogen atom to the resulting molecular fragments. The Fischer–Tropsch (FT) process consists of the reaction of a synthesis gas (syngas) mixture containing carbon monoxide (CO) and hydrogen (H2), which are polymerized into liquid hydrocarbon chains (alkane), often using a cobalt catalyst hence the correct answer is B.

Q84. How much phosphorus is required by an adult man per day?

• A. 500 mg
• B. 400 mg
• C. 800 mg✓
• D. 1800 mg

Explanation: Phosphorus is a mineral that makes up 1% of a person's total body weight. It is the second most abundant mineral in the body. It is present in every cell of the body. Most of the phosphorus in the body is found in the bones and teeth. It is advised that a healthy adult gets between 800mg and 1200mg of phosphorus each day.

Q85. How many sodium ions (Na+) will be pumped out, when IO-postassium ions (K+) are transported inward of resting member potential.

• A. 5
• B. 10
• C. 15✓
• D. 20

Explanation: Known as the Na+/K+ pump or Na+/K+-ATPase, this is a protein pump found in the cell membrane of neurons (and other animal cells). It acts to transport sodium and potassium ions across the cell membrane in a ratio of 3 sodium ions out for every 2 potassium ions brought in. Therefore for 10 potassium ions, 15 sodium ions will be pumped outside.

Q86. At absolute zero the molecules of hydrogen gas will have:

• A. Only translational motion
• B. Only vibrational motion
• C. Only rotational motion
• D. All the motion are ceased✓

Explanation: At absolute zero, the molecules of hydrogen gas will have all motions ceased. This is because absolute zero is the lowest possible temperature, and at this temperature, all molecular motion stops. This includes translational motion, rotational motion, and vibrational motion. At absolute zero, the molecules of hydrogen gas will be perfectly still. They will not be moving at all, and they will not be vibrating. They will simply exist in a state of zero energy. It is important to note that absolute zero is a theoretical temperature, and it is impossible to reach in practice. However, scientists have been able to get very close to absolute zero, and they have been able to study the properties of matter at these very low temperature.

Q87. A dilute hydrochloric acid is added to a flask containing time stone a gas is produced which is dissolved in time water in a test tube a white precipitate is formed the precipitate is of:

• A. CaSO4
• B. CaCO3✓
• C. CaCl2
• D. MgCO3

Explanation: The precipitate that is formed is CaCO3. When dilute hydrochloric acid is added to a time stone, a gas is produced. This gas is carbon dioxide (CO2). The CO2 gas is then dissolved in time water, which forms a solution of carbonic acid (H2CO3). The carbonic acid then reacts with calcium ions in the time stone to form a white precipitate of calcium carbonate CaCO3.

Q88. 2XeF6 + SiO2 --> 2XeOF4 + SiF4 Consider the above chemical reaction. If 122.6 g of XeF6 reacts with 60 g of SiO2 to form the products. Select the limiting reagent and amount of SiF4 formed: (XeF6 245.3 amu, SiO2 = 60 amu, SiF4 = 104 amu)

• A. XeF6, 26 g✓
• B. SiO2, 26 g
• C. XeF6, 52 g
• D. SiO2, 52 g

Explanation: The first step is to find the moles of each reactant. The molar mass of XeF6 is 245.3 g/mol, so 122.6 g of XeF6 is equal to 0.4986 moles. The molar mass of SiO2 is 60 g/mol, so 60 g of SiO2 is equal to 1 mol. The balanced chemical equation tells us that 2 moles of XeF6 react with 1 mole of SiO2. Since we have less moles of XeF6 than SiO2, XeF6 is the limiting reagent. This means that all of the XeF6 will be consumed in the reaction, and SiO2 will be the excess reagent. To find the amount of SiF4 formed, we need to use the moles of XeF6 as a conversion factor. We know that 2 moles of XeF6 produce 1 mole of SiF4, so 0.4986 moles of XeF6 will produce 0.2493 moles of SiF4. The mass of SiF4 produced is equal to its moles multiplied by its molar mass, which is 104 g/mol. So, 0.2493 moles of SiF4 will have a mass of 25.5 g. Therefore, the limiting reagent is XeF6 and the amount of SiF4 formed is 25.5 g. Here is a summary of the results: Limiting reagent: XeF6 Amount of SiF4 formed: 25.5 g

Q89. Ethanal reacts with CH3CH2Mg Br the product formed is:

• A. Option A
• B. Option B
• C. Option C✓
• D. Option D

Explanation: The reaction between ethanal (CH3CHO) and CH3CH2MgBr is an example of a Grignard reaction. Grignard reagents, such as CH3CH2MgBr, are organometallic compounds that can react with carbonyl compounds, such as aldehydes and ketones, to form alcohols. In this case, the reaction can be represented as follows: CH3CHO + CH3CH2MgBr → CH3CH(OH)CH2CH3

Q90. Which is not true about Grignard reagent?

• A. They are highly reactive compounds
• B. They are very stable compounds and can be isolated easily✓
• C. They have synthetic importance
• D. They are represented by general formula RMgX.

Explanation: The statement that is not true about Grignard reagents is They are very stable compounds and can be isolated easily. Grignard reagents are highly reactive compounds and must be handled with care. They are typically prepared in situ, just before they are used, and they cannot be isolated.

Q91. Choose reaction that is not correct?

• A. Option A
• B. Option B
• C. Option C✓
• D. Option D

Explanation: When acetic acid reacts with phosphorus pentoxide, acetic anhydride is formed. Therefore, the correct reaction is Option C.

Q92. XYZ are the elements in the same short period of the periodic table the oxide of X is amphoteric the Exide of Y is basic and the Exide of Z is acidic what is the order of increasing atomic number for these elements?

• A. XYZ
• B. XZY
• C. YXZ✓
• D. ZXY

Explanation: In a period basic nature decreases and the acidic nature increases of the oxides along the period hence the arrangement should be YXZ hence Y has the least atomic number followed by X and Z having the highest atomic number.

Q93. In which of the following reaction hydrogen acts as oxidizing agent.

• A. H2 + Cl2 --> 2HCl
• B. C2H4 + H2 --> C2H6
• C. 2Na + H2 --> 2NaH✓
• D. N2 + 3H2 --> 2NH3

Explanation: 2Na(s) → 2Na+ (g) + 2e– (Oxidation) and the other half-reaction is H2(g) + 2e– → 2H– (g) (Reduction) So, it is evident that sodium is oxidized and hydrogen is reduced in this reaction. Hence the correct answer is C.

Q94. The correct order of the reactivity of hydrocarbon given below is:

• A. C2H4> C2H2> C6H6✓
• B. C6H6> C2H4> C2H2
• C. C2H4> C2H4> C6H6
• D. C2H2> C6H6> C2H4

Explanation: The reactivity order depends on the process. 1) In acid-base reactions, alkynes are the most reactive followed by alkenes and alkanes. This is due to the stability of the conjugate base of alkyne by sp hybridized carbon atom. 2)In electrophilic substitution, alkynes are less reactive than alkenes. It is because of the relative stability of carbocation formed in the case of alkenes. Also, the C atom in alkyne is more electronegative (more s character) due to which, it tightly holds π electrons. 3)In the case of hydrogenation reactions, alkynes are more reactive than alkenes.

Q95. How many oxygen atoms are present in 278g of Hydrated Ferrous Sulphate? (FeSO4.7Hz 0 = 278 any)

• A. 6.023 x 1023
• B. 6.525 x 1024✓
• C. 2.408 x 1023
• D. 6.023 x 1022

Explanation: 4 oxygen comes from sulfate ion and 7 oxygen from water in hydrated ferrous sulfate solution hence there is a total of 11 oxygen molecules. Upon multiplying them with Avogadro’s number 6.023x1023x 11=6.625x 1024 we get the answer B.

Q96. The compound Aldehyde hydrazone is:

• A. Option A✓
• B. Option B
• C. Option C
• D. Option D

Explanation: Aldehyde hydrazones are organic compounds derived from aldehydes and hydrazine (NH2-NH2) or its derivatives. They are formed by the reaction between an aldehyde and hydrazine, where the hydrazine adds across the carbonyl group of the aldehyde, resulting in the formation of a hydrazone. The general structure of an aldehyde hydrazone is RH > CH = N-NH2, where RH represents the organic group attached to the carbonyl carbon of the aldehyde.

Q97. Which is the correct IUPAC name of the compound given below?

• A. Acetophenon
• B. Phenylethanone✓
• C. Phenyl ethanal
• D. Phenylacetate

Explanation: Acetophenone also known as “phenyl methanone” is a methyl ketone that is acetone in which one of the methyl groups has been replaced by a phenyl group.

Q98. Chromium compounds in which oxidation state of chromium is 2+ behaves as a:

• A. Strong oxidizing agent
• B. Strong reducing agent✓
• C. Very weak oxidizing agent
• D. Very weak reducing agent

Explanation: Chromium compounds in which the oxidation state of chromium is 2+ behave as strong reducing agents. This is because chromium in the +2 oxidation state has a relatively low electronegativity, which means that it is easily oxidized. When chromium in the +2 oxidation state is oxidized, it gains electrons and becomes chromium in the +3, +4, or +6 oxidation state. Strong reducing agents are those that readily donate electrons. They are often used in chemical reactions to reduce other elements or compounds. For example, chromium(II) sulfate can be used to reduce silver ions to silver metal.

Q99. Primary amines on treatment with alkyl halide yield;

• A. Secondary amine
• B. Tertiary amine
• C. Quaternary ammonium salt
• D. Mixture of (a), (b) & (c)✓

Explanation: Primary amines on treatment with alkyl halide yield a mixture of secondary amine, tertiary amine, and quaternary ammonium salt. The reaction is a nucleophilic substitution reaction, in which the nitrogen atom of the amine attacks the halogen atom of the alkyl halide. The reaction can be represented by the following equation: RNH2 + R'X → RNHR' + HX In the first step of the reaction, the nitrogen atom of the amine donates a pair of electrons to the halogen atom of the alkyl halide. This forms a new bond between the nitrogen atom and the alkyl group, and it also releases the halide ion. The halide ion is then removed from the solution. In the second step of the reaction, the nitrogen atom of the amine can react with another molecule of alkyl halide. This forms a new bond between the nitrogen atom and the second alkyl group, and it also releases another halide ion. The halide ion is then removed from the solution. The reaction can continue in this way to form a tertiary amine or a quaternary ammonium salt. The exact product that is formed depends on the concentration of the amine and the alkyl halide. The reaction of primary amines with alkyl halides is a very important reaction in organic chemistry. It is used to synthesize a variety of secondary, tertiary, and quaternary amines. The reaction is also used to make drugs, dyes, and other organic compounds.

Q100. The total energy of a hydrogen atom in its ground state is:

• A. Zero
• B. Negative✓
• C. Positive
• D. None of the above

Explanation: The total energy of a hydrogen atom in its ground state can be calculated using the Schrödinger equation, which is a fundamental equation in quantum mechanics. The ground state of a hydrogen atom refers to the lowest energy state that the electron can occupy. In the Bohr model of the hydrogen atom, the ground state energy can be expressed as: E = -13.6 eV / n2 Where: E is the energy of the ground state in electron volts (eV), n is the principal quantum number, which is equal to 1 for the ground state. Plugging in the values: E = -13.6 eV / (12) = -13.6 eV So, the total energy of a hydrogen atom in its ground state is approximately -13.6 electron volts.

Q101. Choose reaction that does not require ZnCl3 catalyst:

• A. CH3CH2OH + HCl --> CH3CH2Cl + H2O✓
• B. CH3CH2OH + HBr --> CH3CH2Br + H2O
• C. CH3CH2OH + Hl --> CH3CH2l + H2O
• D. Both (b) & (c)

Explanation: The reaction of alcohol with HCl is completed in the presence of a ZnCl2 catalyst which forms the basis of the Lucas test for the alcohol. Hence the correct answer is A.

Q102. Select the correct reaction of the following:

• A. SnO + 4NaOH --> Sn(OH)4 + 2Na2O
• B. SnO + 4NaOH --> Na4Sn (OH)4
• C. SnO + 2NaOH --> Na2Sn (OH)4
• D. None of the above✓

Explanation: SnO + 2NaOH → Na2SnO2 + H2O Tin(II) oxide reacts with sodium hydroxide to produce stannate(II) sodium and water.

Q103. Choose the true statement regarding the reaction given below 2Na(g) + Cl2(g)--> 2NaCl(s)

• A. Chloride is oxidized and sodium is reduced
• B. Chlorine acts as an oxidizing agent and sodium as reducing agent✓
• C. Chlorine acts as a reducing agent and
• D. None of the above

Explanation: In the reaction given below: 2Na(s)+Cl2(g)⟶2NaCl(s) 0 0 +1 -1 Na is oxidized to Na+and hence, Cl2 is the oxidizer. Therefore the correct answer is B.

Q104. What are the values of principal quantum number and azimuthal quantum number for the last electron in Chlorine atom?

• A. 1.6
• B. 1.3
• C. 3.1✓
• D. 6.1

Explanation: The electronic configuration of the chlorine is [Ne]3s23p5. Therefore the quantum numbers for chlorine are principal quantum number (n) is 3, azimuthal quantum number (l) = 1.

Q105. Kp = Kc (RT)△n in the equation if △n < 0 then:

• A. Kp = Ke
• B. Kp<Ke✓
• C. Kp>Ke
• D. Kp< 0

Explanation: Kp And Kc are the equilibrium constants of an ideal gaseous mixture. Kp is the equilibrium constant used when equilibrium concentrations are expressed in atmospheric pressure and Kc is the equilibrium constant used when equilibrium concentrations are expressed in molarity. When the change in the number of moles of gas molecules is less than zero, that is Δn < 0⇒ Kp<Kc.

Q106. Shown below are portion of orbital diagrams representing the ground state electronic configuration of certain elements. Which of them obeys the Pauli‘s exclusion principle and Hund‘s rules?

• A. Option A
• B. Option B
• C. Option C
• D. Both option B and C are correct✓

Explanation: Options A and D are incorrect because two electrons with the same spin are not added to the same orbitals.

Q107. Chemical shift in NMR spectroscopy is expressed as delta (δ) or tan (t) scale. Choose the correct relationship between δ and t:

• A. δ = 10 – t✓
• B. δ = 10 + t
• C. t = δ – 10
• D. t = 10 – δ

Explanation: The correct relationship between chemical shift in NMR spectroscopy, expressed as δ (delta), and tan (t) scale is: δ = 10 - t

Q108. Choose the correct statement: DDT an insecticide is considered as:

• A. Very unstable molecule having half-life 1⁄2 to 1 year
• B. Unstable molecule having half-life 2 to 5 years
• C. Stable molecule having half-life 5 to 8 years
• D. Very stable molecule having half-life 10 to 15 years✓

Explanation: Dichlorodiphenyltrichloroethane (hereinafter referred to as DDT) is one of the most widely used and well-studied pesticides ever synthesized. DDT is highly environmentally stable with a reported half-life of between 2 and 15 years. Hence the most suitable answer is D.

Q109. Select meta directing group of the following?

• A. –OH
• B. – NR2
• C. –CN✓
• D. –OR

Explanation: Meta directing group withdraws the electron from the ortho and para position making benzene less reactive. The incoming electrophile then prefers to attack the meta position. The meta-directing group includes NO2, COOH, CHO, SO3H, CN, COR, etc. Hence the correct answer is C. All others are ortho and para-directing groups.

Q110. The osmotic pressure of dilute solution is given below by relationship:

• A. A
• B. B✓
• C. C
• D. D

Explanation: The correct relationship for the osmotic pressure of a dilute solution is: π = RCT/M In this equation, π represents the osmotic pressure, R is the ideal gas constant, T is the temperature in Kelvin, C is the molar concentration of the solute, and M is the molar mass of the solute. The equation relates the osmotic pressure of a dilute solution to the temperature, concentration, and molar mass of the solute.

Q111. Choose the one which is not the assumption of collision theory of reaction rate:

• A. For chemical reaction to occur molecule/ particles must colloids✓
• B. For reacting molecules/ Particles must possess a certain minimum amount of energy, the activation of energy
• C. Every collision is not productive
• D. For hydrogen molecule formation from atoms require specific orientation

Explanation: The assumption that For chemical reaction to occur molecule/ particles must colloids is not correct. The collision theory of reaction rate assumes that for a chemical reaction to occur, the reacting particles must collide with sufficient energy and with the proper orientation. The term "colloids" refers to a type of suspension of particles in a liquid, and it is not necessary for the reacting particles to be in a colloid in order for a reaction to occur. The correct assumptions of the collision theory of reaction rate are: The reacting particles must collide with sufficient energy. This energy is called the activation energy. The reacting particles must collide with the proper orientation. This means that the atoms or molecules must be in a position where they can react with each other. Not every collision is productive. This means that even if the reacting particles collide with sufficient energy and with the proper orientation, the reaction may not still occur. This is because there is a chance that the collision will not be energetic enough to break the bonds in the molecules, or that the molecules will not be able to rearrange themselves in the correct way to form the products.

Q112. A neutron with K.E equal to 0.04ev is called?

• A. Slow neutron✓
• B. Thermal neutron
• C. Fast neutron
• D. Both (a) and (b)

Explanation: Slow neutron, neutron whose kinetic energy is below about 1 electron volt (eV), which is equal to 1.60217646 10−19 joules. Hence the correct answer is A.

Q113. Radiation damages living organism is primarily due to:

• A. Excitation phenomena
• B. Ionization
• C. Photo electric effect
• D. Heating
• E. All of them✓

Explanation: The answer is All of them. Radiation can damage living organisms by causing a variety of effects, including: Excitation: This is when radiation knocks electrons out of their atoms, leaving them in an excited state. The electrons can then fall back to their ground state, releasing energy in the form of heat or light. Ionization: This is when radiation removes electrons from atoms, leaving them as ions. Ions are unstable and can react with other molecules, causing damage. Photoelectric effect: This is when radiation knocks electrons out of atoms, freeing them to move around. This can disrupt the function of proteins and other molecules. Heating: Radiation can also cause heating, which can damage cells and tissues. All of these effects can damage living organisms, and the severity of the damage depends on the type of radiation, the dose, and the sensitivity of the organism. For example, high-energy radiation, such as gamma rays, can cause ionization and excitation, which can lead to cell death. Low-energy radiation, such as ultraviolet light, can cause the photoelectric effect, which can damage proteins and DNA. The effects of radiation on living organisms can be acute, meaning that they occur immediately after exposure, or they can be chronic, meaning that they occur over time. Acute effects of radiation can include burns, nausea, vomiting, and hair loss. Chronic effects of radiation can include cancer, genetic damage, and premature aging. It is important to note that not all radiation is harmful. Some types of radiation, such as X-rays, are used in medicine to diagnose and treat diseases. However, it is important to be aware of the risks of radiation exposure and to take steps to minimize your exposure.

Q114. Pka values of some acids are given below: Choose the weaker acid?

• A. HClO4 (–10)
• B. HBr (–9)
• C. H2SO4 (–3)✓
• D. HCl (–7)

Explanation: The relationship between Ka, pKa, and acid strength is as follows: the lower the Ka value, the higher the pKa value, and the weaker the acid. If Ka is high (and pKa is low), the acid is largely dissociated and therefore powerful. Strong acids have a pKa less than or equal to -2. When Ka is low (and pKa is high), there has been little dissociation, hence the acid is weak. Weak acids have a pKa in water that ranges from -2 to 12. Hence the correct answer is C.

Q115. The water formed in the combustion analysis is usually absorbed by:

• A. Mg (NO3)2
• B. Mg (ClO4)2✓
• C. Mg (OH)2
• D. Mg (ClO2)2

Explanation: Drying agents (hygroscopic) are the type of chemical substances that absorb moisture from their surroundings. Magnesium perchlorate is also a hygroscopic substance that heavily absorbs moisture from its environment and heavily dissolves the water in itself. Hence B is the correct answer

Q116. When small amount of ammonia is added to CUSO4 solution in water, blue PPt of [Cu(H2O)4(OH)2] is formed. The blue PPt dissolves on addition of excess of ammonia. The product formed is:

• A. [Cu(H2O)2 (NH3)2 (OH)2]
• B. [Cu(NH3)4 (OH)2]
• C. [Cu (NH3)4 (H2O)2]2+✓
• D. [Cu (NH3)3 (H2O3]2+

Explanation: Ammonia acts as both a base and a ligand. The ammonia replaces the water as a ligand to give tetraamminediaquacopper II ions. Hence C is the correct answer.

Q117. Graphite is one of the allotropic form of Carbon it is:

• A. Isotropic
• B. Anisotropic
• C. Bond conductor of electricity
• D. Both (b) & (c)✓

Explanation: Graphite is one of the allotropic forms of carbon, and it is known to be anisotropic and a good conductor of electricity. Anisotropic refers to a material that exhibits different properties or behaviors in different directions. In the case of graphite, it has a layered crystal structure with strong covalent bonds within each layer, but weak forces between the layers. As a result, graphite has different properties along different crystallographic directions. Graphite's ability to conduct electricity is due to its unique structure. Within each layer of graphite, carbon atoms are arranged in a hexagonal lattice, forming strong covalent bonds. However, between the layers, there are weaker van der Waals forces, which allows for the easy movement of electrons along the layers. This property makes graphite an excellent electrical conductor.

Q118. If one Faraday was to be 30,230 coulombs instead of 96,500 coulombs then charge on an electron is:

• A. 1.5 x 10–19C
• B. 1 x 10–19C
• C. 0.5 x 10–19C✓
• D. 6.02 x 10–19C

Explanation: If 30,230 C = 1 mol E = 6.02 x 10 23 E, then 1 E = 30,230/6.02 x 10 23 = 5.0 x 10-20 =0.5 x 10-19

Q119. In the CH3CH2C = CH + H2O ->?

• A. CH3CHO + CH3CHO
• B. CH3CH2CH2CH2 – OH
• C. CH3CH2CH2COOH
• D. CH3CH2COCH3✓

Explanation: The addition of the elements of water across the triple bond of an alkyne leads to the formation of aldehydes and ketones. Hence the correct answer is D.

Q120. Which statement is correct for three way catalytic converter:

• A. Reduces emission of unburnt HC‘s
• B. Reduces pollutants
• C. Oxidize pollutant like CO
• D. All of the above✓

Explanation: The correct statement is ALL OF THE ABOVE. A three-way catalytic converter is a device that is used to reduce emissions from internal combustion engines. It does this by using a catalyst to speed up chemical reactions that convert harmful pollutants into less harmful substances. The three main pollutants that a three-way catalytic converter reduces are: Nitrogen oxides (NOx): These are formed when nitrogen and oxygen in the air react at high temperatures. NOx can cause respiratory problems and contribute to smog. Carbon monoxide (CO): This is a colorless, odorless gas that is produced when fuel is not burned completely. CO can reduce the amount of oxygen in the blood, which can lead to headaches, dizziness, and even death. Hydrocarbons (HC): These are compounds that contain hydrogen and carbon. HC can contribute to smog and can also be harmful to human health. A three-way catalytic converter uses a combination of platinum, palladium, and rhodium to speed up the reactions that convert these pollutants into less harmful substances. The catalyst works by providing a surface on which the reactions can occur more easily. The three-way catalytic converter is a very effective way to reduce emissions from internal combustion engines. It can reduce NOx emissions by up to 90%, CO emissions by up to 95%, and HC emissions by up to 99%.

Q121. Which of the following are components of homeostatic mechanism;

• A. Receptor, Regulators, Effectors
• B. Receptors, Integrator, Effectors✓
• C. Sensors, Brain, Effectors
• D. All of the above

Explanation: The correct answer is Receptor, Integrator, Effectors. The three components of a homeostatic mechanism are: Receptor: This is the part of the system that detects changes in the environment. For example, the body's temperature receptors detect changes in the body's temperature. Integrator: This is the part of the system that processes the information from the receptor and determines whether a change is needed. For example, the brain is the integrator for the body's temperature control system. Effector: This is the part of the system that takes action to correct the change. For example, the sweat glands are effectors in the body's temperature control system.

Q122. The electronic transition that is involved in the visible region is:

• A. A
• B. B✓
• C. C
• D. D

Explanation: The electronic transition that is involved in the visible region of the electromagnetic spectrum is typically associated with d-d transitions. These transitions occur when an electron in a d orbital of a metal ion moves from one d orbital to another within the same energy level.

Q123. A water sample contains 3.8 x 103g of mercury per kilo gram of the sample. What is the concentration of mercury in parts per million?

• A. 3.8 ppm✓
• B. 38 ppm
• C. 0.38 ppm
• D. 380 ppm

Explanation: 3.8 x 103/ 1000= 3.8ppm

Q124. Select the reaction when the supply of air is very limited;

• A. CH4 + 202->CO2 + 2H2O + heat
• B. 2CH4 + 3O2-> 2CO2 + 4H2O + heat
• C. CH3 – CH3 + 7O2-> CO2 + 6H2O + heat
• D. 2CH4 + 2O2-> 2CO + 4H2O + heat✓

Explanation: Limited supply of oxygen leads to incomplete combustion of alkanes resulting in the formation of carbon-monoxide and water. Hence the correct answer is D.

Q125. The main components of lipstick are:

• A. Mixture of non-volatile oil and solid wax
• B. Mixture of volatile oil and wax
• C. Fats and wax
• D. Fates, oil and wax✓

Explanation: he primary ingredients found in lipstick are wax (beeswax, candelilla wax, or the more expensive carnauba), oil (caster, lanolin, or vegetable oil), alcohol, fragrance, pigment, preservatives, and antioxidants hence the correct answer is D.

Q126. Which of the following solution will have

• A. 1 molar solution of urea✓
• B. 1 molar solution of glucose
• C. 1 molar solution of sodium chloride
• D. 1 molar solution of magnesium chloride

Explanation: The explanation for this question will be added soon.

Q127. The spin states of a nucleus of an atom in absence of applied magnetic field have:

• A. Different energies
• B. Equal energies✓
• C. Zero energies
• D. High energies

Explanation: In the absence of an applied magnetic field, the spin states of a nucleus of an atom have equal energies. The spin states of a nucleus refer to the different possible orientations of the nuclear spin angular momentum vector. These states have the same energy level in the absence of an external magnetic field. However, when an external magnetic field is applied, the energy levels of these spin states split, and this phenomenon is known as nuclear Zeeman splitting. The energy difference between the split energy levels is proportional to the strength of the applied magnetic field.

Q128. The Sulphur Bacteria which obtain energy by oxidizing H2S instead of water is called:

• A. Alpha proteobacteria
• B. Beta proteobacteria
• C. Gamma proteobacteria✓
• D. Gamma proteobacteria

Explanation: The sulfur bacteria that obtain energy by oxidizing H2S instead of water are called chemolithotrophic sulfur bacteria. They are a type of gamma proteobacteria. Gamma proteobacteria are a large and diverse group of bacteria that includes many different types of organisms, including sulfur bacteria, cyanobacteria, and pathogens. They are found in a wide variety of environments, including soil, water, and the human body. Chemolithotrophic sulfur bacteria are able to use inorganic sulfur compounds, such as H2S, as their energy source. They do this by oxidizing the sulfur compounds, which releases energy that the bacteria can use to grow and reproduce. There are two main types of chemolithotrophic sulfur bacteria: aerobic and anaerobic. Aerobic bacteria require oxygen to oxidize sulfur compounds, while anaerobic bacteria can do so without oxygen. Chemolithotrophic sulfur bacteria are important in the environment because they help to cycle sulfur. They also have potential applications in biotechnology, such as in the production of bioethanol and biohydrogen.

Q129. The ground state energy of H-atom is 13.6 eV. The energy needed to lonize H-atom from its second excited state is:

• A. 1.51 eV✓
• B. 3.4 eV
• C. 13.6 eV
• D. 12.1 eV

Explanation: Ionization energy, also called ionization potential, in chemistry and physics, is the amount of energy required to remove an electron from an isolated atom or molecule. There is an ionization energy for each successive electron removed. For a hydrogen atom, composed of an orbiting electron bound to a nucleus of one proton, an ionization energy of 2.18 × 10−18 joule (13.6 electron volts) is required to force the electron from its lowest energy level entirely out of the atom. When the hydrogen is in a second excited state, the value of n is equal to 3. Therefore, the radius of a hydrogen atom when it is in its second excited state is nine times its radius when it is in its ground state, and the energy associated with it is 1.51eV. Hence A is the correct answer.

Q130. The path traced by beta particles in air is:

• A. Straight
• B. Erratic✓
• C. Circular
• D. Elliptical

Explanation: The path traced by beta particles in air is erratic. Beta particles are high-speed electrons that are emitted from the nucleus of an atom during radioactive decay. As they travel through air, they interact with the air molecules, causing them to change direction and lose energy. This results in a zigzag or erratic path. The path of beta particles can be affected by a number of factors, including the energy of the beta particle, the density of the air, and the presence of a magnetic field. In a strong magnetic field, beta particles will be deflected in a circular path. However, in air, the magnetic field is not strong enough to have a significant effect on the path of beta particles. The erratic path of beta particles makes it difficult to track their movement. However, this erratic motion can also be used to advantage in some applications, such as in smoke detectors.

Q131. Read the statement carefully and choose the correct option.

• A. 0.693/k✓
• B. 0.693/2k
• C. log2/k
• D. In2/k

Explanation: Half life is inversely proportional in second order reaction.

Q132. What is the concentration moles/liter of nitric acid solution having PH of 4?

• A. 4
• B. -4
• C. 10-4✓
• D. 10-10

Explanation: To calculate the concentration of moles per liter (molarity) of a nitric acid solution with a pH of 4, we need to use the relationship between pH and the concentration of hydrogen ions (H+). The pH is defined as the negative logarithm (base 10) of the hydrogen ion concentration ([H+]): pH = -log[H+] To find the concentration of H+ ions, we can rearrange the equation: [H+] = 10^(-pH) Now, we can plug in the pH value (4) into the equation: [H+] = 10^(-4) [H+] = 0.0001 moles per liter (mol/L) Since nitric acid (HNO3) dissociates in water to produce one H+ ion for each molecule of HNO3, the concentration of nitric acid is the same as the concentration of H+ ions. So, the concentration of nitric acid in moles per liter is 0.0001 mol/L.

Q133. Ethoxy ethane when treated with conc: H2SO4 it produces:

• A. Carbocation
• B. Oxonium ion✓
• C. Carbanion
• D. Oxalate ion

Explanation: An oxonium ion is any cation containing an oxygen atom that has three bonds and a 1+ formal charge. Ethoxy ethane when reacts with conc H2SO4 gives a lone pair making oxonium ion.

Q134. What is the formula of Dichloro-Bis-ethylenediamine cobalt (II)?

• A. [CO (en)2 Cl2]✓
• B. [CO (en)2 Cl2]2–
• C. [CO (ebn)2 Cl2]1–
• D. [CO (en)2 Cl2]1+

Explanation: The formula of Dichloro-Bis-ethylenediamine cobalt (II) is: [CoCl2(en)2] In this formula: Co represents the cobalt metal center. Cl2 indicates that there are two chloride ions (Cl-) coordinated to the cobalt atom. (en)2 indicates that there are two ethylenediamine (en) ligands coordinated to the cobalt atom. The ethylenediamine ligand is represented by the abbreviation "en" and is a bidentate ligand, meaning it can bind to the metal center through two nitrogen atoms.

Q135. Lithium reacts with air to form:

• A. Li2O
• B. Li2N
• C. Li2O2 + Li2CO3
• D. Both (a) & (b)✓

Explanation: Lithium burns with a strongly red-tinged flame if heated in the air. It reacts with oxygen in the air to give white lithium oxide. With pure oxygen, the flame would simply be more intense. 4Li + O2 = 2Li2O For the record, it also reacts with the nitrogen in the air to give lithium nitride. Lithium is the only element in this Group to form a nitride in this way. 6Li + N2 =2Li3N

Q136. What will be the shape of a molecule which contains two sigma bond pairs and one lone pair?

• A. Linear
• B. V shape
• C. Tetragonal
• D. Triangular✓

Explanation: A molecule with two sigma bond pairs and one lone pair will have a trigonal planar molecular geometry. This molecular shape occurs when there are three regions of electron density around the central atom. The two sigma bond pairs form bonds with other atoms, and the lone pair is a non-bonding pair of electrons localized on the central atom. These three electron regions try to arrange themselves in a way to minimize repulsion, resulting in a planar arrangement with bond angles of approximately 120 degrees. A classic example of a molecule with this molecular geometry is the molecule of boron trifluoride (BF3). Boron has three sigma bonds with three fluorine atoms, and there is one lone pair of electrons on the boron atom. The molecular shape of BF3 is trigonal planar, and its bond angles are approximately 120 degrees.

Q137. Which of the following electronic configuration is/arecorrect? (i) 23Na 1s22s22P63s1(ii)29Cu [Ar] 4s13d10(iii)24Cr [Ar] 4s23d4

• A. I only
• B. I and III only
• C. I and II only✓
• D. II and III only

Explanation: The sodium electron configuration will be 1s22s22p63s1 The electronic configuration of copper is [Ar] 3d¹⁰ 4s¹ The electronic configuration of chromium is [Ar] 3d⁵ 4s¹

Q138. Which of the following is spontaneous reaction?

• A. A✓
• B. B
• C. C
• D. D

Explanation: To determine if a reaction is spontaneous, we can compare the standard cell potential (E°) of the reaction with zero. If the standard cell potential is positive (greater than zero), the reaction is spontaneous under standard conditions. In this reaction, the reduction potential of Cu²+ (+0.34V) is greater than the reduction potential of Zn²+ (-0.76V). This means Cu²+ is a stronger oxidizing agent than Zn²+. Therefore, the reaction is spontaneous. Zn + Cu²+ → Zn²+ + Cu

Q139. Choose atom that is not having a spin quantum number 1/2:

• A. C13
• B. N15
• C. F19
• D. O16✓

Explanation: The atom that does not have a spin quantum number of 1/2 is O16. The other three atoms, C13, N15, and F19, all have an odd number of protons and neutrons so, they have spin quantum numbers of 1/2. The spin quantum number is a property of subatomic particles, such as protons, neutrons, and electrons. It describes the intrinsic angular momentum of the particle. The spin quantum number can have a value of 1/2 or -1/2. The nucleus of the atom O16 has an even number of protons and neutrons, so it has a spin quantum number of 0. Therefore, the answer to the question is O16.

Q140. Select the correct reaction.

• A. A
• B. B
• C. C✓
• D. D

Explanation: Phenyl amine forms Diazonium salt under these conditions.

Q141. Excess of BaSO4 was dissolved in pure water at 250C. If its Ksp = 1 x 10–10 what is the Conc: of Ba2+ ions in water?

• A. 10–10
• B. 10–20
• C. 10–5✓
• D. 10–6

Explanation: Ksp = [Ba2+] [ SO24 - ] 1 x 10-10 = (x) (x) 10-5=x

Q142. The total energy of a particle executing S.H.M. is:

• A. Inversely proportional to the square of the amplitude
• B. Directly proportional to the amplitude
• C. Zero
• D. Directly proportional to the square of the amplitude✓

Explanation: The type of motion in which the acceleration of the body is always directly proportional to the displacement of the body from mean position and is always directed towards the mean position is called simple harmonic motion. E= ½The total energy of a particle executing S.H.M. is directly proportional to the square of the amplitude. So the answer is directly proportional to the square of the amplitude. The total energy of a particle executing SHM is given by the equation: E = (1/2)mω2A2 where: E is the total energy m is the mass of the particle ω is the angular frequency of the oscillation A is the amplitude of the oscillation As you can see, the total energy is directly proportional to the square of the amplitude. This means that the total energy of the particle will increase quadratically as the amplitude increases. For example, if the amplitude is doubled, the total energy will quadruple. This is because the potential energy of the particle is proportional to the square of the displacement from the equilibrium position, and the kinetic energy of the particle is proportional to the square of the velocity. As the amplitude increases, both the potential energy and the kinetic energy increase, and the total energy increases quadratically.

Q143. A weight suspended from an ideal spring oscillates up and down with a period T. If the amplitude of the oscillation is doubled, the period will be:

• A. T✓
• B. 1
• C. 2T
• D. T

Explanation: Time period will not change as it is independent of amplitude so the answer is 'T'.

Q144. A heat engine:

• A. Converts heat input to an equivalent amount of work✓
• B. Converts work to an equivalent amount of heat
• C. Takes heat in, doeswork, and loses energy as heat
• D. Uses positive work done on the system to transfer heat from a low temperature reservoir to a high temperature reservoir

Explanation: A heat engine is a device that converts heat energy into mechanical work. Steam engines,petrol engines and diesel engines,are all examples of heat engines.

Q145. If 50 KV is the applied potential in ax X-ray tube then the minimum wavelength of X-rays produced is:

• A. 0.2 nm
• B. 2 nm
• C. 0.02 nm✓
• D. 2A

Explanation: GIVEN: Applied voltage:50-kv=50 x103 V Plank’s constant=6.626 x10-34 Js Charge on electron=1.6 x10-19 C Speed of light=3x108 m/s REQUIRED: Shortest wavelength ‘𝝺’=? SOLUTION: 𝝺min=hc/qev PUTTING VALUES 𝝺min=6.626 x 10-34 Js 3x108 ms-1 / 1.6x10-19 C x 50.0x103 V 𝝺min=62.1875 x 10-10 𝝺min =0.0282nm

Q146. Two projectiles are in flight at the same time. The acceleration of one relative to the other:

• A. Is always 9.8 m/s2
• B. Can be as large as 19.8 m/s2
• C. Can be horizontal
• D. Is zero✓

Explanation: The acceleration of one projectile relative to the other is zero. The acceleration of a projectile is always pointing downwards, due to the force of gravity. The acceleration of one projectile relative to the other is the difference between their respective accelerations. Since both projectiles are accelerating downwards at the same rate, the acceleration of one projectile relative to the other is zero. In other words, if you were sitting in one projectile and you looked at the other projectile, you would not see it accelerating. It would appear to be moving in a straight line. This is because the relative velocity between the two projectiles is constant.

Q147. In Compton scattering from stationary electrons the largest change in wavelength occurs when the photon is scattered through:

• A. 00
• B. 450
• C. 900
• D. 1800✓

Explanation: The largest change in wavelength occurs when the photon is scattered through 180 degrees. So the answer is (d). The Compton effect is the scattering of a photon by an electron. When a photon is scattered by an electron, it loses some of its energy to the electron. This causes the wavelength of the photon to increase. The amount of wavelength shift depends on the scattering angle. The larger the scattering angle, the greater the wavelength shift. At a scattering angle of 180 degrees, the photon is scattered back in the direction it came from. This means that all of the energy of the photon is transferred to the electron, and the wavelength of the photon increases by the maximum amount.

Q148. If the potential difference across a resistor is doubled:

• A. Only the current is doubled✓
• B. Only the current is halved
• C. Only the resistance is doubled
• D. Only the resistance is halved

Explanation: The answer is only the current is doubled. This is because of Ohm's law, which states that the current through a resistor is directly proportional to the potential difference across the resistor. In other words, if the potential difference is doubled, the current will also be doubled. The resistance of the resistor will stay the same, so the only thing that will change is the current.

Q149. Nuclear fusion in the sun is increasing in supply of:

• A. Hydrogen
• B. Helium✓
• C. Nucleons
• D. Positrons

Explanation: Nuclear fusion in the sun is the process by which hydrogen atoms are combined to form helium atoms. This process releases a large amount of energy, which is what powers the sun. The supply of hydrogen in the sun is vast, but it is not infinite. As the sun fuses hydrogen atoms, it produces helium atoms. So the answer is (b), helium.

Q150. The functional group region in infra-red spectrum lies between:

• A. 500 – 1300cm–1
• B. 600 – 1500cm–1
• C. 1500 – 4000cm–1✓
• D. 2500 – 3500cm–1

Explanation: The functional group region in an infrared spectrum is the region where the absorption bands of functional groups are found. The functional group region is typically between 1500 and 4000 cm-1. This is because the vibrations of functional groups tend to occur in this region.

Q151. In stationary waves:

• A. There is not transfer of energy
• B. Energy is constant at all points
• C. Phase is the same for all points
• D. Both (a) & (b)✓

Explanation: In a stationary wave, there is no net transfer of energy. This is because the energy is alternately transferred from one point to another, but it does not travel in any particular direction. The energy is also constant at all points in a stationary wave. This is because the energy is evenly distributed between the two waves that are interfering to create the stationary wave.

Q152. If each vector have unit magnitude than ⃗A. ⃗A is:

• A. South
• B. One✓
• C. North
• D. West

Explanation: The answer is one. The dot product of two vectors is a scalar quantity that represents the product of the magnitudes of the two vectors and the cosine of the angle between them. If each vector has a unit magnitude and the angle between them is 0 degrees, then the dot product is equal to one. Here is the formula for the dot product of two vectors: A⃗.B⃗=|A⃗||B⃗|cosθ where: A⃗ and B⃗ are the two vectors |A⃗| and |B⃗| are the magnitudes of the two vectors θ is the angle between the two vectors If each vector has a unit magnitude, then |A⃗| = |B⃗| = 1. If the angle between the two vectors is 0 degrees, then cosθ = 1. Therefore, the dot product is equal to 1.

Q153. In a purely resistive circuit the current:

• A. Leads the voltage by one-half of a cycle
• B. Leads the voltage by one-fourth of a cycle
• C. Leads the voltage by one-half of a cycle
• D. Is in phase with the voltage✓

Explanation: The answer is (d), is in phase with the voltage. In a purely resistive circuit, the current and voltage are in phase with each other. This means that the current reaches its peak at the same time as the voltage, and the current troughs at the same time as the voltage troughs. The reason for this is that the resistance in a purely resistive circuit does not cause any phase shift between the current and voltage. The resistance simply converts the electrical energy from the voltage source into heat energy.

Q154. The number of ejected photoelectrons increases with increase.

• A. In intensity of flight✓
• B. In wavelength of light
• C. In frequency of light
• D. Never

Explanation: The number of ejected photoelectrons increases with an increase in the intensity of light. This phenomenon is explained by the photoelectric effect, where photons of light (quanta of electromagnetic energy) interact with a material, causing the ejection of electrons from the material's surface. The intensity of light refers to the number of photons striking the material per unit area per unit time. When the intensity of light increases, more photons are incident on the material, leading to a greater number of photoelectrons being emitted.

Q155. The number of loops in the standing waves is directly dependent on:

• A. Wavelength
• B. Frequency✓
• C. Velocity
• D. Speed

Explanation: Explanation below

Q156. In Einstein‘s universe what is the fourth dimension:

• A. Distance
• B. Speed
• C. Time✓
• D. Energy

Explanation: Einstein's theory of relativity, both special and general, introduced the concept of spacetime as a unified four-dimensional framework in which three dimensions of space (length, width, height) and one dimension of time are combined. This revolutionized our understanding of the relationship between space and time, showing that they are interconnected and cannot be fully separated. In this view, an event in spacetime is described by four coordinates: three for spatial location and one for the time at which the event occurs. The concept of spacetime is a fundamental element of Einstein's theories and has been confirmed through various experimental observations and measurements, including time dilation and gravitational effects.

Q157. A.C and D.C have the same:

• A. Affect in charging battery✓
• B. Affect in charging capacitor
• C. Heating effect through a resistance
• D. Affect passing through an inductance

Explanation: The correct option is "Effect in charging battery." Charging a battery with both AC and DC currents can have a similar effect in terms of replenishing the battery's energy storage. However, the charging process and efficiency might vary between AC and DC due to factors such as the battery chemistry, charging circuitry, and voltage regulation. It's important to note that while the overall effect of charging a battery can be similar, the underlying mechanisms and technical considerations might differ between AC and DC charging methods.

Q158. Which is strong electrolyte?

• A. Ca(OH)2
• B. SiCI4
• C. KCl✓
• D. SrCl2

Explanation: KCl is a strong electrolyte. A strong electrolyte is a substance that completely dissociates into ions when dissolved in water. This means that all of the molecules of the substance break apart into ions, which are then free to move around in the solution. Strong electrolytes are good conductors of electricity because the ions can carry the charge.

Q159. X-rays are widely used as a diagnostic tool in medicine because of its:

• A. Particle property
• B. Cost of X-ray unit is low
• C. High penetrating power✓
• D. It is not electromagnetic waves

Explanation: X-rays are a type of electromagnetic radiation that can pass through most objects, including the human body. When x-rays hit human tissue, they produce an image that can be used to detect medical conditions. An X-ray procedure and x-ray equipment are used to diagnose and treat medical conditions, as they can: Diagnose broken bones – one of the most common uses for this type of medical imaging. Detect other medical conditions, such as tumors, internal bleeding, or cancer detection (such as breast cancer). X -rays have high penetrating power. X -rays have high frequencies of the range 10 power 16 Hz to 10 power 20 Hz. According to Planck's equation for energy of a photon, E=hυ E= Energy of photon h=planck's constant=6.63×10-34 Js υ=Frequency of photon in Hertz Hence, energy of a photon, E is directly proportional to the frequency of a photon,υ E∝υ Now,since X-rays have high frequency, consequently they have high energy. And therefore high penetrating power. ∴ X-rays have high penetrating power because of their high frequency.

Q160. To obtain greater dispersion by a diffraction grating:

• A. The slit width should be increased
• B. The slit width should be decreased
• C. The slit separation should be increased
• D. The slit separation should be decreased✓

Explanation: Decreasing the slit separation would also result in a decrease in the dispersion achieved by the diffraction grating. When the slits are closer together, the angular separation between the diffracted orders would decrease, leading to less spread of colors or wavelengths in the resulting pattern. This would reduce the ability of the diffraction grating to separate different wavelengths effectively.

Q161. The unit ―henry‖ is equivalent to:

• A. Volt-second/ampere✓
• B. Volt/second
• C. Ohm
• D. Ampere volt/ second

Explanation: The unit "henry" (H) is the standard unit of inductance in the International System of Units (SI). It is defined as the amount of inductance in a circuit where an electromotive force of one volt is produced when the current in the circuit changes at a rate of one ampere per second. Therefore, the unit "henry" is equivalent to "volt-second/ampere," which reflects the relationship between voltage, current change rate, and inductance.

Q162. A total charge of 100C flows through a 12W bulb in a time of 50 second. What is the potential difference across the bulb during this time?

• A. 0.12V
• B. 2.0V
• C. 6.0V✓
• D. 24V

Explanation: The potential difference (voltage) across a device can be calculated using Ohm's Law: V=I×R where: V is the potential difference (voltage) across the device, I is the current flowing through the device, R is the resistance of the device. In this case, we have a 12W (watt) bulb. The power P in watts can be related to current I and resistance R by the formula: P=I 2 ×R Given that the power of the bulb is 12W and the current flows for 50 seconds (which implies a total charge of 100C), we can solve for the resistance R: 12W=I2 ×R Since Q=I×t (where Q is the charge, I is the current, and t is time), and we're given that Q=100C and t=50s, we can solve for I: I= Q/t= 100C / 50s=2A Now we can substitute I=2A into the power equation to find R: 12W=(2A)2 ×R R= 12W / 4A2 =3Ω Now that we have the resistance R and the current I, we can calculate the potential difference V using Ohm's Law: V=I×R=2A×3Ω=6V So, the correct answer is: 6.0V

Q163. Becquerel is the unit of:

• A. Decay constant
• B. Half life
• C. Mean life
• D. Activity✓

Explanation: The Becquerel (Bq) is the unit of radioactivity or activity. It measures the rate at which a radioactive substance undergoes decay. One Becquerel represents one decay event per second. This unit is named after Henri Becquerel, a physicist who discovered radioactivity.

Q164. The changing electric flux in a certain region of space produces:

• A. An electric field
• B. Magnetic field
• C. both A and B✓
• D. None of the above

Explanation: A changing electric flux does indeed produce a magnetic field, as explained by Faraday's law. However, it doesn't directly produce an electric field. The relationship between changing electric flux and induced magnetic field is significant and described by electromagnetic induction. When the magnetic flux through a circuit changes, a nonconservative electric field is induced, which drives current through the circuit. So, changing electric flux produces magnetic ifeld which produces electric field. Hence, option C is correct.

Q165. A laser beam can be sharply focused because it is:

• A. Highly coherent
• B. Plane polarized
• C. Intense
• D. Highly directional✓

Explanation: A laser is a device that emits light through a process of optical amplification based on the stimulated emission of electromagnetic radiation. The word "laser" is an acronym for "light amplification by stimulated emission of radiations A laser differs from other sources of light in that it emits light which is coherent. Laser light is highly directional as a laser beam spreads very little;it departs from strict parallelism only because of diffraction at the exit aperture of the laser.Whereas ordinary light spreads.

Q166. A charged capacitor stores 10 C at 40 V.. Its stored energy is:

• A. 400 J
• B. 4 J
• C. 0.2 J
• D. 200 J✓

Explanation: GIVEN: Q=10C V=40V REQUIRED: Energy stored=U=? SOLUTION: U=QV/2 U=1/2 (10C х 40V) U=200 J

Q167. A hydrogen atom that has lost its electron is moving east in a region where the magnetic moving east in a region where the magnetic fields directed from south to north. It will be deflected:

• A. Up
• B. Down
• C. North
• D. South✓

Explanation: A hydrogen atom that has lost its electron is moving east in a region where the magnetic field is directed from south to north will be deflected south. This is because the moving electron will experience a magnetic force that is perpendicular to both its direction of motion and the direction of the magnetic field. The direction of the magnetic force can be determined using Fleming's left-hand rule. According to Fleming's left-hand rule, the thumb points in the direction of the current, the index finger points in the direction of the magnetic field, and the middle finger points in the direction of the force. In this case, the current is in the east direction, the magnetic field is in the north direction, and the force is in the south direction. So, the hydrogen atom will be deflected south.

Q168. The colour of thin films is a result of:

• A. Dispersion
• B. Absorption of light
• C. Scattering of light
• D. None of the above✓

Explanation: The answer is (d). The color of thin films is not a result of any of the options listed. The color of thin films is a result of interference. This means that the light waves reflected from the top and bottom surfaces of the film interfere with each other, and the colors you see are due to the interference patterns that are produced. The colors that you see depend on the thickness of the film, the wavelength of the light, and the angle of incidence of the light. If the thickness of the film is a multiple of half the wavelength of the light, then constructive interference occurs, and you see a bright color. If the thickness of the film is an odd multiple of quarter the wavelength of the light, then destructive interference occurs, and you see a dark color. This is why thin films can appear to be different colors depending on the angle of view. As you rotate the thin film, the thickness of the film changes, and the colors that you see change. However, none of these processes are the primary reason why thin films appear to be different colors. The color of thin films is a result of interference, which is a different process altogether.

Q169. Read the statement carefully and choose the correct option.

• A. 80Hz✓
• B. 800Hz
• C. 8000Hz
• D. 50Hz

Explanation: The reactance (XL) of an inductor is given by the formula: XL=2πfL Where: XL is the inductive reactance, f is the frequency of the AC signal (in hertz), L is the inductance of the inductor (in henrys). Given that the inductance L is 1 henry and the reactance XL is 500 ohms, we can solve for the frequency f: 500Ω=2πf.1H Solving for f: f= 500Ω/2π ≈79.577Hz So, the closest option is: 80Hz

Q170. A vector of magnitude 20 is added to a vector of magnitude 25. The magnitude of this sum might be:

• A. Zero
• B. 3
• C. 12
• D. 47✓

Explanation: The magnitude of the sum of two vectors can be determined using the triangle law of vector addition. This law states that if two vectors are represented as sides of a triangle, then the sum of the two vectors can be represented by the third side of the triangle. In this case, if a vector of magnitude 20 is added to a vector of magnitude 25, the magnitude of the sum could be anywhere between ∣20−25∣=5 (if the two vectors are in opposite directions) and 20+25=45 (if the two vectors are in the same direction). Out of the given options, the closest one to the potential range of magnitudes is: 47 However, it's important to note that the exact magnitude of the sum will depend on the relative directions of the two vectors. The magnitude will be smaller if they are opposing and larger if they are aligned.

Q171. The time period of a simple pendulum is 2 seconds. If its length is increased by 4 times, then its period becomes:

• A. 16 sec
• B. 12 sec
• C. 8 sec
• D. 4 sec✓

Explanation: T=2π √ l/g T∝ √ l As we know that T1 is 2s so, l=1m If the length is increased by 4 times T1/T2 = √ l1/l2 2s/T2= √ 1m/4m 2s/T2=1/2 BY CROSS MULTIPLICATION T2=4 sec

Q172. A moving charged particle is surrounded by?

• A. 1 fields
• B. 3 fields✓
• C. 2 fields
• D. 4 fields

Explanation: A moving charged particle is surrounded by three fields.These fields are:Electric Field: The electric field is created by the charged particle itself due to its charge. It exerts a force on other charged particles in the vicinity.Magnetic Field: The magnetic field is generated by the moving charged particle. A moving charged particle creates a magnetic field around it. The strength and direction of this field depend on the velocity of the particle.Electromagnetic Field: When a charged particle is in motion, its electric field and magnetic field are interrelated and combine to form an electromagnetic field. This field carries energy and can propagate through space as electromagnetic waves.

Q173. Water flows from a 6.0cm diameter pipe into 8.0cm diameter pipe. The speed in the 6.0cm pipe is 5.0m/s. the speed in the 8cm pipe is:

• A. 2.8m/s✓
• B. 3.7m/s
• C. 6.6m/s
• D. 8.8m/s

Explanation: GIVEN: Diameter of 1st pipe= 6.0cm r1=d/2= 6/2=3 Diameter of 2nd pipe=8.0 cm r2=d/2=8/2=4 V1=5.0m/s REQUIRED: V2=? SOLUTION: A1V1 = A2V2 (A=𝛑r2) 𝛑 r12 . v1 = 𝛑 r22. v2 32. 5 = 42 . v2 45=16.v2 v2=45/16 v2=2.8m/s

Q174. The infrared spectra commonly referred to as IR spectra is usually expressed as:

• A. Wave length
• B. Wave number
• C. Frequency
• D. All of the above✓

Explanation: The answer is (d). Infrared spectra, commonly referred to as IR spectra, are usually expressed as wavelength, wavenumber, or frequency. Wavelength: This is the distance between two consecutive peaks in the spectrum. Wavelengths of infrared radiation range from about 700 nanometers (nm) to 1 millimeter (mm). Wavenumber: This is the reciprocal of the wavelength, and it is expressed in units of reciprocal centimeters (cm-1). Wavenumbers are often used in IR spectroscopy because they are independent of the physical properties of the sample, such as its temperature and pressure. Frequency: This is the number of waves that pass a given point in space per unit time. Frequencies of infrared radiation range from about 1013 to 1014 hertz (Hz). The choice of which unit to use depends on the specific application. Wavelength is often used when comparing spectra from different sources, such as different materials or different conditions. Wavenumber is often used when calculating the energies of molecular vibrations, which are related to the wavenumber of the IR absorption. Frequency is often used when calculating the speed of IR radiation, which is related to the frequency of the radiation. In general, IR spectra can be expressed in any of the three units, but wavelength, wavenumber, and frequency are the most common.

Q175. A particle, held by a string whose other end is attached to a fixed point C, moves in a circle on a horizontal frictionless surface. If the string is cut, the angular momentum of the particle about the point: C.

• A. Increases
• B. Decreases
• C. Does not change✓
• D. Changes direction but not magnitude

Explanation: The angular momentum of the particle about the point C will not change if the string is cut. This is because the angular momentum of a particle is conserved if there is no external torque acting on the particle. When the string is cut, there is no external torque acting on the particle, so the angular momentum of the particle is conserved. The angular momentum of a particle is defined as the product of the particle's momentum and its distance from the axis of rotation. In this case, the axis of rotation is the point C. When the string is cut, the particle will continue to move in a circle, but the radius of the circle will increase. This will cause the particle's momentum to decrease, but the product of the particle's momentum and its distance from the axis of rotation will remain the same. So, the angular momentum of the particle will not change.

Q176. An electron has charge (e) and mass (m). A proton has charge e and mass 1840m. A "Proton volt" is equal to:

• A. A
• B. B
• C. C✓
• D. D

Explanation: A proton volt is equal to (1/1840) eV. An electron volt is the energy gained by an electron when it is accelerated through a potential difference of 1 volt. The energy of a proton is equal to the energy of an electron multiplied by its charge-to-mass ratio. The charge-to-mass ratio of a proton is about 1840 times greater than the charge-to-mass ratio of an electron. So, the energy of a proton is about 1/1840 times less than the energy of an electron. Therefore, a proton volt is equal to (1/1840) eV. Here is the calculation: Proton volt = eV/q/m= eV * m/q= eV * 1840 m/(e * 1840 m)= (1/1840) eV

Q177. The rotational inertia of a disk about its axis is 0.70 Kg. m2. When a 2.0-kg weight is added to its rim, 0.40m from the axis, the rotational inertia becomes:

• A. 0.38 Kg – m2
• B. 0.54 kg – m2
• C. 0.86 kg – m2
• D. 1.0 kg – m2✓

Explanation: The moment of inertia of the disc about the axis O is IO=0.7kgm2 The moment of inertia of the mass is Im=mr2=2⋅0.42=0.32kgm2 The total moment of inertia is I=IO+Im=0.7+0.32=1.02kgm2

Q178. Which of the following is closest to a yard:

• A. 0.01 m
• B. 0.1 m
• C. 1 m✓
• D. 100 m

Explanation: A yard is one such unit to measure length. One yard is equal to 0.9144 meters. 1m is closest to 0.9 so option C is correct Yard= 0.914m=1m

Q179. You stand on a spring scale on the floor of an elevator. Of the following, the scale shows the highest reading when the elevator:

• A. Moves upward with increasing speed✓
• B. Moves upward with decreasing speed
• C. Remains stationary
• D. Moves downward with increasing speed

Explanation: The scale shows the highest reading when the elevator moves upward with increasing speed. This is because the spring scale measures the normal force that is exerted on you by the floor of the elevator. When the elevator is moving upward with increasing speed, the normal force is greater than when the elevator is moving upward with decreasing speed, or when it is moving downward with increasing speed, or when it is stationary. The reason for this is that when the elevator is moving upward with increasing speed, you are accelerating upwards. This means that there is a net force acting on you in the upwards direction. The normal force from the floor of the elevator is what counteracts this net force and keeps you from accelerating upwards indefinitely. The greater the acceleration, the greater the normal force must be. In contrast, when the elevator is moving upward with decreasing speed, or when it is moving downward with increasing speed, or when it is stationary, there is no net force acting on you. This means that the normal force from the floor of the elevator is equal to your weight. So, the scale shows the highest reading when the elevator moves upward with increasing speed because the normal force is greatest in this case.

Q180. A wheel starts from rest and has an angular acceleration of 4.0 rad/s2. When it has made 10 rev its angular velocity is:

• A. 16 rad/s
• B. 22 rad/s✓
• C. 32 rad/s
• D. 250 rad/s

Explanation: a = 4 rad/s2 S = 10 rev = 62.83 rad Where is the final angular velocity, the initial angular velocity, a is the angular acceleration and S the radians. We get: = 22.41rad/s

Q181. Signal from a remote control to the device operated by it, travels with the speed of:

• A. Sound
• B. Supersonic
• C. Ultrasonic
• D. Light✓

Explanation: Signal from a remote control to the device operated by it travels with the speed of light. The first thing you notice about a remote control unit is that it has no wires, so it has to send signals to whatever it's operating using electromagnetic waves. Light, X rays, radio waves, and microwaves are all examples of electromagnetic waves: vibrating packets of electrical and magnetic energy that travel through the air at the speed of light. Most remote controls send signals using infrared radiation (which is a kind of invisible red light that hot objects give off and halogen hobs use to cook with), though some use radio waves instead. If you look at the top of your remote control unit, you'll see there's a small plastic light-emitting diode (LED) where the infrared radiation comes out. Now take a look at your TV or video. Somewhere on the front, there's a very small infrared light detector. When you press the remote control, a beam of infrared radiation travels from the remote to your TV at the speed of light and the detector picks it up.

Q182. Which of the following electromagnetic waves has the smallest wavelength?

• A. X-rays
• B. Gamma rays✓
• C. Microwaves
• D. Ultraviolet rays

Explanation: Gamma rays have the smallest wavelength of all the electromagnetic waves. Electromagnetic waves are arranged in a spectrum according to their wavelength. The wavelength of an electromagnetic wave is the distance between two consecutive peaks of the wave. Gamma rays have the shortest wavelength, followed by x-rays, ultraviolet rays, visible light, infrared rays, microwaves, and radio waves.

Q183. The temperature coefficient of resistance of a semiconductor is:

• A. Positive
• B. Negative✓
• C. Imaginary
• D. Zero

Explanation: The temperature coefficient of resistance of a semiconductor is negative. It means that resistance decreases with increase of temperature. This results in a higher number of charge carriers available for recombination, increasing the conductivity of the semiconductor. The increasing conductivity causes the resistivity of the semiconductor material to decrease with the rise in temperature, resulting in a negative temperature coefficient of resistance.

Q184. Angle that a body traverses at the centre of a circle in two turns is:

• A. A
• B. B
• C. C
• D. D✓

Explanation: To determine the angle that a body traverses at the centre of a circle in two turns, we need to calculate the total angle covered. In one complete revolution (one turn) around a circle, the angle covered is 360° or 2π radians. Since we are considering two turns, we can simply multiply the angle for one turn by 2. So, the angle covered in two turns is: 2 turns × 360 degrees/turn = 720 degrees 2 turns × 2π radians/turn = 4π radians Therefore, the correct answer is D, as both 720 degrees and 4π radians represent the angle that a body traverses at the centre of a circle in two turns.

Q185. Two tuning forks of frequencies 256Hz and 260Hz are sounded together the time interval between two consecutive maximum sound heard by a listener is:

• A. 0.5 Sec
• B. 2 Sec
• C. 1 Sec
• D. 0.25 Sec✓

Explanation: Δf= 260-250 Δf=4 Hz T=1/ Δf T=1/4s-1 T=0.25 sec

Q186. Intrinsic semi-conductor can be converted into extrinsic semi-conductor by adding:

• A. Trivalent impurity
• B. Pentavalent impurity
• C. Pentavalent or trivalent impurities✓
• D. None of the above

Explanation: SEMICONDUCTOR: A semiconductor substance has an electrical property that sits between an insulator and a conductor. Si and Ge are the greatest examples of semiconductors. INTRINSIC SEMICONDUCTOR: Semiconductors in which the number of electrons is equal to the number of holes are intrinsic semiconductors. CONVERSION OF INTRINSIC SEMICONDUCTOR TO EXTRINSIC SEMICONDUCTOR: When a small amount of suitable impurity is added to the intrinsic semiconductor we can convert it into an extrinsic semiconductor of either p-type or n-type. Doping changes the concentration of charge carriers in the element. i) P- type: When Si or Ge is doped with any trivalent impurity like Al, B etc we get a p-type semiconductor. The dopant has one valence electron less. Thus, this atom forms a covalent bond with the neighbouring three atoms and, is less of one electron to offer to the fourth silicon atom and as a result there is a vacancy. Hence, an electron in the outer orbit of the neighbouring atom may jump to fill this vacancy leaving a vacancy or hole at its own site. This hole is the conducting charge carrier. Therefore, doping with a trivalent impurity gives us p-type semiconductor. ii) N - type: When we dope Si or Ge with pentavalent impurities like As, P then four electrons of this atom will form covalent bonds with the neighbouring Si atom in the lattice. Whereas, the fifth electron will remain loosely bound to its parent atom. Hence, the ionisation energy which is required to make this electron free is very less and it will move around even at room temperature. Thus, the pentavalent dopant will donate one extra electron for conduction and this acts as an n-type semiconductor. Extrinsic semiconductors are semiconductors that have had an impurity introduced to them at a regulated rate to make them conductive.

Q187. A 30-cm long string, with one end clamped and the other free to move transversely, is vibrating in its second harmonic. The wavelength of the constituent traveling waves is:

• A. 10 cm
• B. 30 cm
• C. 40 cm✓
• D. 120 cm

Explanation: Option C is the correct answer

Q188. An object of mass 1 g is whirled in a horizontal circle of radius 0.5m at a constant speed of 2m/s. The work done on the object during one revolution is:

• A. 0✓
• B. 1 J
• C. 2 J
• D. 4 J

Explanation: When an object moves in a circular path at a constant speed, the centripetal force is responsible for keeping it in that path. The centripetal force does not do any work on the object because the force is always perpendicular to the displacement of the object at any point in the circular motion. As a result, the work done by the centripetal force is zero. In this scenario, since the object is moving at a constant speed in a horizontal circle, the centripetal force is responsible for changing the direction of the velocity but not its magnitude. The force is always directed toward the center of the circle, and the displacement of the object is tangential to the circle. Therefore, the angle between the force and displacement vectors is 90 degrees, making the work done by the centripetal force zero. So, the correct answer is (a) 0 J.

Q189. A mass accelerates uniformly when the resultant force acting on it is:

• A. Zero
• B. Constant but not zero✓
• C. Increases uniformly with respect to time
• D. Both (a) & (c)

Explanation: A mass accelerates uniformly when the resultant force acting on it is constant but not zero. If the resultant force is zero, the mass will not accelerate and will either remain at rest or move with uniform speed. If the resultant force increases uniformly with respect to time, the mass will accelerate at an increasing rate. This is in accordance with Newton's second law of motion, which states that the acceleration of an object is proportional to the resultant force acting on it and inversely proportional to the mass of the object. So, if the resultant force is constant, the acceleration will also be constant.

Q190. In Young‘s double slit experiment both the separation between the slits and the distance between the slits and the screen are halved; then the fringe width is:

• A. Halved
• B. Unchanged✓
• C. Doubled
• D. Zeros

Explanation: In Young's double-slit experiment, the fringe width (the distance between adjacent bright or dark fringes on the screen) is given by the formula: wavelength * distance_to_screen / distance_between_slits Where: wavelength is the wavelength of light used in the experiment. distance_to_screen is the distance between the double slits and the screen. distance_between_slits is the separation between the two slits. Let's analyze the given situation: If both the separation between the slits and the distance between the slits and the screen are halved: The separation between the slits (distance_between_slits) becomes half of its original value. The distance between the slits and the screen (distance_to_screen) also becomes half of its original value. Now, let's consider how these changes affect the fringe width formula: Fringe width = wavelength * (distance_to_screen) / (distance_between_slits) If both distance_to_screen and distance_between_slits are halved, they cancel each other out in the formula. This means that the changes in the two distances will have no net effect on the fringe width. Mathematically: Fringe width = wavelength * (0.5 * distance_to_screen) / (0.5 * distance_between_slits) = wavelength * (distance_to_screen) / (distance_between_slits) The fringe width remains unchanged despite halving both distances. So, the correct answer is (b) Unchanged.

Q191. In pure inductance, the average power dissipated is:

• A. 1
• B. Greater than 1
• C. Less than 1
• D. Zero✓

Explanation: The average power dissipated in a pure inductance is zero. This is because the instantaneous power in a pure inductance is equal to the product of the instantaneous voltage and the instantaneous current, and the instantaneous current in a pure inductance is always 90 degrees out of phase with the instantaneous voltage. Therefore, the average power dissipated is zero. So the answer is (d). Here is a more detailed explanation: The instantaneous power in a pure inductance is given by: P = vi where: P is the instantaneous power v is the instantaneous voltage i is the instantaneous current In a pure inductance, the instantaneous current is always 90 degrees out of phase with the instantaneous voltage. This means that the product of v and i is always zero, and the average power dissipated is zero.

Q192. As a loop of wire with a resistance of 10Ω moves in a constant non-uniform magnetic field, it loses kinetic energy at a uniform rate of 4.0 ms/s. The induced current in the loop is:

• A. 0
• B. 2 mA
• C. 2.8 mA✓
• D. 20 mA

Explanation: The induced current in the loop is 2.8 mA. The rate of loss of kinetic energy is equal to the power dissipated in the loop, which is given by: P = I2R where: P is the power dissipated I is the induced current R is the resistance of the loop We are given that the rate of loss of kinetic energy is 4.0 ms^-1, and the resistance of the loop is 10 mΩ. Solving for the induced current, we get: I = sqrt(P/R) = sqrt(4.0/10) = 2.8 mA Therefore, the induced current in the loop is 2.8 mA.

Q193. Two objects, P and Q have the same momentum. Q has more kinetic energy than P if it:

• A. Weighs more than P
• B. Is moving faster than P✓
• C. Weighs the same as P
• D. Is moving slower than P

Explanation: Two objects with the same momentum have different kinetic energies if they have different speeds. If Q is moving faster than P, then it has more kinetic energy than P. So the answer is (b). Here is the explanation: The momentum of an object is given by: p = mv where: p is the momentum m is the mass of the object v is the speed of the object The kinetic energy of an object is given by: KE = (1/2)mv2 where: KE is the kinetic energy m is the mass of the object v is the speed of the object If two objects have the same momentum, then they have the same mass. However, if Q is moving faster than P, then it has more kinetic energy than P. This is because the kinetic energy is proportional to the square of the speed. So, if the speed is doubled, the kinetic energy is quadrupled. Therefore, if Q is moving faster than P, then it has more kinetic energy than P.

Q194. A child, riding on a large merry-go-round, travels a distance of 3000m in a circle of diameter 40m. the total angle through which she revolves is:

• A. SO rad
• B. 75 rad
• C. 150 rad✓
• D. 314 rad

Explanation: The total angle through which the child revolves is equal to the arc length divided by the radius of the circle. The arc length is the distance traveled by the child, which is 3000 m. The radius of the circle is half the diameter, which is 20 m. So, the total angle through which the child revolves is: arc length / radius = 3000 m / 20 m = 150 rad Therefore, the answer is (c). Here is a more detailed explanation: The angle through which an object revolves is equal to the arc length divided by the radius of the circle. The arc length is the distance traveled by the object along the circumference of the circle. The radius is the distance from the center of the circle to the object. In this case, the arc length is 3000 m, and the radius is 20 m. So, the total angle through which the child revolves is: arc length / radius = 3000 m / 20 m = 150 rad

Q195. The value of work done by the spring force may be:

• A. All of these✓
• B. Zero
• C. Positive
• D. Negative

Explanation: If the particle connected to the spring is moving from an extreme position towards a mean position, work done by the spring force is positive. If the particle is moving from the mean position towards the extreme position, work done by the spring force is negative. But while calculating work done the displacement from the initial position to the final position need to be considered. Thus, overall work done in a single cycle can be zero since the displacement would be zero.

Q196. In water pipes _ is used to detect leakages.

• A. Radiation✓
• B. Light
• C. Current
• D. None of these options are correct

Explanation: Radiation is used to detect leakages in water pipes.There are two main types of radiation that are used to detect water leaks:Radioactive tracers: A radioactive tracer is a substance that is injected into the water supply. The tracer is then tracked using a radiation detector. If there is a leak, the tracer will be detected at the site of the leak.Sound waves: Sound waves can be used to detect water leaks by listening for the sound of escaping water. This method is not as accurate as radioactive tracers, but it is less expensive and can be used in areas where radioactive tracers are not allowed.

Q197. Stationary waves are result of _ travelling in opposite direction waves.

• A. Identical✓
• B. Different
• C. Any of Option A or B
• D. Stationary waves cannot be formed

Explanation: When two plane waves having the same amplitude and frequency,travelling with the same speed in opposite direction along a line,are superposed,a wave obtained is called stationary or standing wave.The sound produced by most string and wind musical instruments is due to the formation of stationary waves or standing waves in these instruments.The vibration in the string of a guitar or piano sets up stationary waves of definite frequencies.Stationary waves can be set up in a medium which does not transmit energy from one place to another place like progressive waves.

Q198. When the source is at the centre of the circle and the observer is moving on the circumference of circle, the sound heard by observer:

• A. Same✓
• B. Different
• C. Increasing
• D. Decreasing

Explanation: Consider the circle,the source is at the centre of the circle and the observer is moving on the circumference of the circle.The observer is not moving towards the centre nor moving away but is moving on the circumference of the circle.The distance from centre to circumference is same at all points so the sound heard by observer is same.

Q199. Newton's third law can be derived from:

• A. Newton's first law
• B. Newton's second law✓
• C. Both Options A and B are correct
• D. They are unrelated

Explanation: Newton's second law gives the definition and mathematical expression of force. By using the expression of force, we can derive Newton's third law. Newton's third law of motion states that for every action, there is an equal and opposite reaction. This means that if object A exerts a force on object B, object B exerts an equal and opposite force on object A. The third law can be derived from the second law by considering the interaction between two objects. When object A exerts a force on object B (according to the second law), object B simultaneously exerts an equal and opposite force on object A. This satisfies the principle of conservation of momentum and leads to Newton's third law. So, the correct answer is option B.

Q200. Molecular theory for metals is also called as:

• A. Electron pool theory
• B. Valence bond theory
• C. Band Theory✓
• D. None of these options are correct

Explanation: The molecular theory for metals is also called as band theory. Band theory is a quantum mechanical model that describes the behavior of electrons in solids. It is based on the idea that the electrons in a solid can be grouped into bands, which are ranges of energy levels that the electrons can occupy. In metals, the valence electrons (the electrons in the outermost shell) are delocalized, which means that they are not bound to any individual atom. Instead, they are free to move throughout the metal. This is why metals are good conductors of electricity. Band theory can be used to explain many of the properties of metals, such as their conductivity, their reflectivity, and their melting point.