Equilibrium · Question 66

In a buffer solution containing equal concentration of B- and HB, the Kb for B- is 10-10. The pH of buffer solution is

1. 10
2. 7
3. 6
4. 4

The dissociation constants for acetic acid and HCN at 25 are 1.5 10-5 and 4.5 10-10 respectively. The equilibrium constant for the equilibrium CN- + CH3COOH HCN + CH3COO- would be

1. 3.3 10-5
2. 3.3 10-4
3. 3.3 104
4. 3.3 105

Which of the following molecules acts as a Lewis acid?

1. (CH3)2O
2. (CH3)3P
3. (CH3)3N
4. (CH3)3B

The ionization constant of ammonium hydroxide is 1.77 10-5 at 298 K. Hydrolysis constant of ammonium chloride is

1. 6.50 10-12
2. 5.65 10-13
3. 5.65 10-12
4. 5.65 10-10

What is the [OH-] in the final solution prepared by mixing 20.0 mL of 0.050 M HCl with 30.0 mL of 0.10 M Ba(OH)2?

1. 0.40 M
2. 0.0050 M
3. 0.12 M
4. 0.10 M

The dissociation equilibrium of a gas AB2 can be represented as: 2AB2(g) 2AB(g) + B2(g) The degree of dissociation is x and is small compared to 1. The expression relating the degree of dissociation (x) with equilibrium constant Kp and total pressure P is

1. (2Kp/P)1/2
2. (Kp/P)
3. (2Kp/P)
4. (2Kp/P)1/3

If the concentration of OH- ions in the reaction Fe(OH)3(s) Fe3+(aq) + 3OH-(aq) is decreased by 1/4 times, then equilibrium concentration of Fe3+ will increase by

1. 64 times
2. 4 times
3. 8 times
4. 16 times

Equal volumes of three acid solutions of pH 3, 4 and 5 are mixed in a vessel. What will be the H+ ion concentration in the mixture?

1. 3.7 10-3 M
2. 1.11 10-3 M
3. 1.11 10-4 M
4. 3.7 10-4 M

The value of equilibrium constant of the reaction HI(g) 12H2(g) + 12I2(g) is 8.0. The equilibrium constant of the reaction H2(g) + I2(g) 2HI(g) will be

1. 16
2. 1/8
3. 1/16
4. 1/64

The values of Kp for the reactions, X Y + Z ....(i) A 2B ....(ii) are in the ratio 9 : 1. If degree of dissociation of X and A be equal, then total pressure at equilibrium (i) and (ii) are in the ratio

1. 36 : 1
2. 1 : 1
3. 3 : 1
4. 1 : 9