Which one of the following is applicable for an adiabatic expansion of an ideal gas?

• $∆$E = 0

• $∆\mathrm{W} = ∆\mathrm{E}$

• $∆\mathrm{W} = -∆\mathrm{E}$

• $∆\mathrm{W} = 0$

102.

The ratio of rates of diffusion of gases X and Y is 1 : 5 and that of Y and Z is 1 : 6. The ratio of rates of diffusion of Z and X is

• 1:30

• 1:6

• 30:1

• 6:1

Which one of the following is the kinetic energy of a gaseous mixture containing 3g of hydrogen and 80g of oxygen at temperature T (K)?

• 3 RT

• 6 RT

• 4 RT

• 8 RT

A, B, C and D are four different gases with critical temperatures 304.1, 154.3, 405.5 and 126.0 K respectively. While cooling the gas, which gets liquefied first?

• B

• A

• D

• C

At 27°C in a 10 L flask 4.0 g of an ideal gaseous mixture containing. He (molar mass 4.0 g mol^-1) and Ne (molar mass 20g mol^-1) has a pressure of 1.23 atm. What is the mass 9 of neon ? (R =0.082 L at K^-1 mol^-1).

• 25.2

• 62.5

• 84.2

• 74.2

The required condition for an ideal solution is

• $∆$H_mix = 0

• $∆$V_mix ≠ 0

• p_A ≠ p°_A X_A

• $∆$H_mix > 1

The vapour pressure decreases by 10 mm of Hg when mole fraction of solute in a solution is 0.2. If the vapour pressure decreases to 20 mm of Hg then the mole fraction of solute will be

• 0.2

• 0.4

• 0.6

• 0.8

The temperature, at which a gas shows maximum ideal behaviour, is known as

• Boyle's temperature

• inversion temperature

• critical temperature

• absolute temperature

A drop of solution (volume 0.05 mL) contains 3 x 10^-6  mole H⁺. If the rate constant of disappearance of H⁺ is 1.0 x 10⁷ molL^-1 s^-1, how long would it take for H⁺ in drop to disappear?

• 4 × 10^-6 s

• 1× 10^-7 s

• 3× 10^-6 s

• 6 × 10^-9 s

van der Waal's equation for n moles of a gas is

• $\left(\mathrm{P} + \frac{{\mathrm{n}}^2\mathrm{a}}{{\mathrm{V}}^2}\right)(\mathrm{V} - \mathrm{nb}) = \mathrm{RT}$

• $\left(\mathrm{P} + \frac{\mathrm{na}}{{\mathrm{V}}^2}\right)(\mathrm{V}\hspace{0.17em}- \mathrm{nb}) = \mathrm{RT}$

• $\left(\mathrm{P} + \frac{\mathrm{a}}{{\mathrm{V}}^2}\right)(\hspace{0.17em}\mathrm{V}\hspace{0.17em}- \mathrm{b}) = \mathrm{RT}$

• $\left(\mathrm{P}\hspace{0.17em}+ \frac{{\mathrm{n}}^2\mathrm{a}}{{\mathrm{V}}^2}\right) (\mathrm{V}\hspace{0.17em}- \mathrm{b})\hspace{0.17em}= \mathrm{RT}$