Chapter 2

According to the kinetic theory of gases, in an ideal gas, between two successive collisions a gas molecule travels (a) in a circular path (b) in a wavy path (c) in a straight line path (d) with an accelerated velocity

Zinc oxide is white when cold, but yellow when hot because it develops (a) Frenkel defect (b) Schottky defect (c) Metal excess defect (d) Metal deficiency defect

In a cubic crystal, what is the total number of planes of symmetry ? (a) 1 (b) 9 (c) 13 (d) 23

The root mean square velocity of an ideal gas at constant pressure varies with density \((d)\) as: (a) \(d^{2}\) (b) \(d\) (c) \(\sqrt{d}\) (d) \(1 / \sqrt{d}\)

For a unit cell, it is given that \(a=10.8 \mathrm{~A}, b=9.46 \mathrm{~A}, c=5.3 \mathrm{~A}\) and also \(\alpha=41^{\circ}, \beta=82.9^{\circ}\), \(y=93.1^{\circ}\). What type of crystal system it belongs to? (a) Monoclinic (b) Triclinio (c) Hexagonal (d) Tetragonal

Equal masses of \(\mathrm{O}_{2}, \mathrm{CH}_{4}\) and He are present in a container. What is the mole fraction of \(\mathrm{CH}_{4}\) ? (a) \(7 / 3\) (b) \(2 / 11\) (c) \(5 / 9\) (d) \(2 / 3\)

KCl is white when cold, but liliac when hot because it develops (a) Frenkel defect (b) Schottky defect (c) Metal excess defect (d) Metal deficiency defect

If an open vessel is heated from \(27^{\circ} \mathrm{C}\) to \(627^{\circ} \mathrm{C}\), what fraction of the molecules of air is left in the vessel ? (a) \(2 / 3\) (b) \(1 / 3\) (c) \(1 / 4\) (d) \(3 / 4\)