Which one of the following is true for any diprotic acid, H₂X?
1. K_a2 = K_a1
2. K_a1 > K_a2
3. K_a1 < K_a2
4. \(K_{a1}=\frac{1}{K_{a2}}\)

One mole of ethyl alcohol was treated with one mole of acetic acid at 25$°$C. 2/3 of the acid changes into ester at equilibrium. The equilibrium constant for the reaction will be:

1. 1                   

2. 2

3. 3                   

4. 4

For a given solution pH = 6.9 at 60$°$C, where K_w=10^-12. The solution is:

1. acidic                                         

2. basic

3. neutral                                         

4. unpredictable

In a buffer solution containing equal concentration of B^- and H B, the K_b for B^- is 10^-10. The pH of buffer solution is 

1. 10

2. 7

3. 6

4. 4

Aqueous solution of acetic acid contains                                                   

1. CH₃COO^- and H⁺

2. CH₃COO^-, H₃O⁺ and CH₃COOH

3. CH₃COO^-, H₃O⁺ and H⁺

4. CH₃COOH, CH₃COO^- and H⁺

The equilibrium, 2SO₂ (g) + O₂ (g) $\rightleftharpoons$2SO₃ (g)

shifts forward if:

1. a catalyst is used

2. an absorbent is used to remove SO₃ as soon as it is formed

3. small amounts of reactants are used

4. none of the above

The pH of blood is maintained by CO₂ by and H₂CO₃ in the body and chemical constituents of blood. This phenomenon is called:

1. colloidal                           

2. buffer action

3. acidic                               

4. salt balance

Incorrect statement among the following is: 

1. Addition of one drop of concentrated HCl in NH₄OH solution decreases pH of the solution.

2. A solution of the mixture of one equivalent of each of CH₃COOH and NaOH has a pH of 7

3. pH of pure neutral water is not zero.

4. A cold and concentrated H₂SO₄ has lower H⁺ ion concentration than a dilute solution of H₂SO₄ 

The rate constants for forward and backward reaction of hydrolysis is ester are 1.1 x10^-2 and 1.5x10^-3 per minute. Equilibrium constant for the reaction,                                                              

 CH₃COOC₂H₅ + H⁺ $\rightleftharpoons$ CH₃COOH + C₂H₅OH is

1. 4.33           

2. 5.33           

3. 6.33         

4. 7.33

What happens to pH of a solution when NH₄Cl crystal is added to a dilute solution of NH₄OH?

1. Decreases                                   

2. Increases

3. Remains unaffected                       

4. All of the above