MDCAT Gases, Liquids & Solids 2026

Gas Laws

• Boyle's law — PV = constant (constant T, n)
• Charles's law — V/T = constant (constant P, n)
• Ideal gas — PV = nRT
• Dalton's law — P_total = ΣP_i

Liquids

• Vapour pressure — increases with T; boiling when = atmospheric P
• Surface tension — cohesive force; capillary action

Solids

• Ionic — NaCl, high mp, brittle, conducts when molten
• Covalent network — diamond, SiO₂, very high mp
• Metallic — sea of electrons, malleable, conducts
• Molecular — iodine, low mp, weak intermolecular forces

Drill Chemistry past papers.