Select the pK_a value of the strongest acid from the following

• 1.0

• 3.0

• 2.0

• 4.5

The compounds A and B are mixed in equimolar proportion to form the products, A +B $\rightleftharpoons$ C+ D. At equilibrium, one third of A and B are consumed. The equilibrium constant for the reaction is

• 0.5

• 4.0

• 2.5

• 0.25

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

304.

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

• HSO${}_4^{-}$

• SO${}_4^{2-}$

• H₃O⁺

• Cl^-

A buffer solution has equal volumes of 0.2 M NH₄OH and 0.02 M NH₄Cl. The pK_b of the base is 5. The pH is

• 10

• 9

• 4

• 7

A precipitate of AgCl is formed when equal volumes of the following are mixed [K_sp for AgCl = 10^-10]

• 10^-4 M AgNO₃ and 10^-7 M HCl

• 10^-5 M AgNO₃ and 10^-6 M HCl

• 10^-5 M AgNO₃ and 10^-4 M HCl

• 10^-6 M AgNO₃ and 10^-6 M HCl

4 moles each of SO₂ and O₂ gases are allowed to react to form SO₃, in a closed vessel. At equilibrium 25% of O₂ is used up. The total number of moles of all the gases at equilibrium is :

• 6.5

• 7.0

• 8.0

• 2.0

Solubility product of a salt AB is 1 x 10^-8 M² in a solution in which the concentration of A⁺ ions is 10M.The salt will precipitate when the concentration of B ions is kept :

• between 10^-8 M to 10^-7 M

• between 10^-7 M to 10^-8 M

• >10^-5 M

• <10^-8 M