Q: What is the molar volume of any ideal gas at STP? A: 22.4 L/mol (at 0°C, 1 atm).

Q: Formula for Boyle temperature? A: T_B = a/(Rb).

Q: Which molecular speed is the smallest? A: v_mp (most probable speed) = $\sqrt{2RT/M}$.

Q: Condition under which Z = 1 for a real gas? A: At very low pressure (P → 0) or at the Boyle temperature over a wide pressure range.

Q: What does 'b' in van der Waals equation represent? A: Excluded volume per mole — correction for finite molecular size; V_free = V - nb.

Q: Critical temperature formula? A: T_c = 8a/(27Rb).

Q: What type of collision is assumed in KMT? A: Perfectly elastic (no energy loss; total kinetic energy conserved).

Q: Relation between average KE and temperature? A: KE = (3/2)RT per mole; depends only on T, not on molar mass.

Q: Effect of increasing temperature on liquid viscosity? A: Viscosity decreases (more KE overcomes intermolecular friction).

Q: Why does $H_{2}$ always show Z > 1? A: Van der Waals 'a' is negligibly small → attraction negligible → only the excluded volume (b) correction matters → Z > 1 always.

Q: What is the Joule-Thomson effect? A: Cooling of a real gas on adiabatic expansion through a porous plug, below the inversion temperature.

Q: What are the three types of intermolecular forces in increasing order of strength? A: London < dipole-dipole < hydrogen bonding.