Equilibrium

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

Equimolar solutions of the following were prepared in water separately. Which one of the solutions will record the highest pH?

1. MgCl2
2. CaCl2
3. SrCl2
4. BaCl2

Which one of the following ionic species has the greatest proton affinity to form stable compound?

1. NH2-
2. F-
3. I-
4. HS-

The equilibrium constants of the following are N2 + 3H2 2NH3; K1 N2 + O2 2NO; K2 H2 + 12O2 H2O; K3 The equilibrium constant (K) of the reaction: 2NH3 + 52O2 2NO + 3H2O will be

1. K2K33/K1
2. K2K3/K1
3. K23K3/K1
4. K1K33/K2

A weak acid, HA, has a Ka of 1.00 10-5. If 0.100 mol of this acid is dissolved in one litre of water, the percentage of acid dissociated at equilibrium is closest to

1. 1.00\%
2. 99.9\%
3. 0.100\%
4. 99.0\%

Calculate the pOH of a solution at 25 C that contains 1 10-10 M of hydronium ions, i.e. H3O+.

1. 4.000
2. 9.000
3. 1.000
4. 7.000

For the reaction : CH4(g) + 2O2(g) CO2(g) + 2H2O(l), Hr = -890.3 kJ mol-1. Which of the following statements is not true?

1. The reaction is exothermic.
2. At equilibrium, the concentrations of CO2(g) and H2O(l) are not equal.
3. The equilibrium constant for the reaction is given by Kp = [CO2][CH4][O2]
4. Addition of CH4(g) or O2(g) at equilibrium will cause a shift to the right.

Which of the following pairs constitutes a buffer?

1. HCl and KCl
2. HNO2 and NaNO2
3. NaOH and NaCl
4. HNO3 and NH4NO3

The hydrogen ion concentration of a 10-8 M, HCl aqueous solution at 298 K (Kw = 10-14) is

1. 1.0 10-8 M
2. 1.0 10-6 M
3. 1.0512 10-7 M
4. 9.512 10-8 M

At 25 , the dissociation constant of a base, BOH, is 1.0 10-12. The concentration of hydroxyl ions in 0.01 M aqueous solution of the base would be

1. 1.0 10-5 mol L-1
2. 1.0 10-6 mol L-1
3. 2.0 10-6 mol L-1
4. 1.0 10-7 mol L-1