Consider the following reactions:

(i) COCl_{2 (g)}  $\leftrightharpoons$CO _(g) + Cl_{2 (g)}

(ii) CO_{2 (g)} + C _(s) $\leftrightharpoons$ 2CO _(g)

(iii) 2H_{2 (g)} + CO _(g) $\leftrightharpoons$ CH₃OH _(g)

Which reaction(s) will shift in a backward direction when the pressure is increased?

1. Only (iii)

2. Only (ii)

3. Both (i) and (ii) 

4. None of the above.

Given an endothermic reaction:

CH_{4 (g)} + H₂O _(g)  $\leftrightharpoons$CO _(g) + 3H_{2 (g)}

If the temperature is increased, then:

1. The equilibrium will not be disturbed.

2. The equilibrium will shift in the backward direction.

3. The equilibrium will shift in the forward direction.

4. None of the above.

For the given reaction: 

PCl_{5 (g)}  $\leftrightharpoons$PCl_{3 (g)} + Cl_{2 (g)}, ∆_rH° = 124.0 kJ mol^–1 and K_c = 8.3 $\times$ 10^-3 mol L^-1 at 473 K

The effect on K_c if (i) pressure is increased  and (ii) the temperature is increased will be, respectively-

1. (i) Will increase; (ii) will decrease

2. (i) Will decrease; (ii) will remain the same 

3. (i) Will remain the same; (ii) will increase

4. (i) will remain the same; (ii) Will decrease

The conjugate acid-base pair is:

1. A pair that differs only by one proton

2. A pair that differs only by the size

3. A pair that differs only by electronegativity

4. None of the above

1. ${\mathrm{HSO}}_4^{-}$, ${\mathrm{CO}}_3^{2-}$

2.  HSO₄^-, CO₃^-

3. SO₄^-2, CO₃^2-

4. HS₂O₄^-, CO₃^2-

The conjugate acids for the Brönsted bases  ${\mathrm{NH}}_2^{-}$ , NH₃ and HCOO^– will be respectively:

1. N₂H₆, NH⁴⁺, HCOOH

2. NH₃, ${\mathrm{NH}}_4^{+}$ , HCOOH

3. NH₃, NH⁴⁺, HCOO₃

4. N₂H, NH⁴⁺, HCOOH

OH^– , F^– , H⁺ and BCl₃

The ionization constants of HCOOH, and HCN at 298K are 1.8 × 10^–4 and 4.8 × 10^–9 respectively. The ionization constants of the corresponding conjugate bases of HCOOH and HCN will be

The ionization constant of phenol is 1.0 × 10^–10. The concentration of phenolate ion in 0.05 M solution of phenol will be:

The first ionization constant of H₂S is 9.1 × 10^–8. The concentration of HS^– ion in its 0.1 M solution will be: