15 moles of H₂ and 5.2 moles of I₂ are mixed and allowed to attain equilibrium at 500°C. At equilibrium, the concentration of HI is found to be 10 moles. The equilibrium constant for the formation of HI is

• 50

• 15

• 100

• 25

If, in the reaction N₂O₄ $\rightleftharpoons$ 2NO₂ ,x is that part of N₂O₄ which dissociates, then the number of molecules at equilibrium will be

• 1

• 3

• (1 + x)

• (1 + x)²

The rate at which a substance reacts depends on its

• atomic weight

• atomic number

• molecular weight

• active mass

Which of the following is an amphoteric acid?

• Glycine

• Salicylic acid

• Benzoic acid

• Citric acid

For the reaction

N₂ (g) + O₂ (g) $\rightleftharpoons$ 2NO (g), the value of K_c at 800°C is 0.1. When the equilibrium concentration of both the reactants is 0.5 mol, what is the value of K_p at the same temperature?

• 0.5

• 0.1

• 0.01

• 0.025

The extent of adsorption of a gas on a solid depends on

• nature of the gas

• pressure of the gas

• temperature of the gas

• all of the above

The species among the following, which can act as an acid and a base is

• HSO${}_4^{-}$

• SO${}_4^{2-}$

• H₃O⁺

• Cl^-

A mixture of two moles of carbon monoxide and one mole of oxygen, in a closed vessel is ignited to convert the carbon monoxide to carbon dioxide. If $∆$H is the enthalpy change and $∆$E is the change in internal energy, then

• $∆\mathrm{H} > ∆\mathrm{E}$

• $∆\mathrm{H} < ∆\mathrm{E}$

• $∆\mathrm{H} = ∆\mathrm{E}$

• the relationship depends on the capacity of the vessel

The cooling in refrigerator is due to

• reaction of the refrigerator gas

• expansion of ice

• the expansion of the gas in the refrigerator

• the work of the compressor

For a system in equilibrium, $∆$G= 0, under conditions of constant ...............

• temperature and pressure

• temperature and volume

• pressure and volume

• energy and volume