The aqueous solution having the lowest pH:

(1) NaOH                 

(2) NH₄Cl

(3) Na₂CO₃               

(4) NaCl

 The following equilibria are given

 N₂ + 3H₂ $\rightleftharpoons$ 2NH₃,      K₁

N₂ + O₂ $\rightleftharpoons$ 2NO,          K₂

H₂ + $\frac{1}{2}$O₂ $\rightleftharpoons$ H₂O,       K₃

The equilibrium constant of the reaction, 2NH₃ + $\frac{5}{2}$O₂ $\rightleftharpoons$ 2NO + 3H₂O in terms of  K₁, K₂ and K₃ is  

1.  $K_{\mathit{1}}{K}_{\mathit{3}}^{\mathit{3}}\mathit{/}{K}_{\mathit{2}}$                         

2.  $K_2{K}_{\mathit{3}}^{\mathit{3}}\mathit{/}{K}_1$

3.  K₁K₂K₃                            

4.  K₁K₂/K₃ 

At a certain temperature, 2HI $\rightleftharpoons$H₂ +I₂ only 50% HI is dissociated at equilibrium. The equilibrium constant is:

(a) 1.0                     (b) 3.0                 (c) 0.5               (d)   0.25

In the reaction, PCl₅$\rightleftharpoons$PCl₃ + Cl₂, the amounts of PCl₅, PCl₃ and Cl₂ at equilibrium are 2 mole each and the total pressure is 3 atm. The equilibrium constant K_p is:

(a) 1.0 atm                                        (b) 2.0 atm

(c) 3.0 atm                                        (d) 6.0 atm

On addition of an inert gas at constant volume to the reaction, N₂ + 3H₂$\rightleftharpoons$2NH₃ at  equilibrium:

(1) the reaction halts

(2) forward reaction is favoured

(3) the reaction remains unaffected

(4) backward reaction is favoured

In which of the following case reaction goes farthest to completion?

(1) K=10³                                         

(2) K=10^-2

(3) K=10                                           

(4) K=10⁰

For the reversible reaction,

N₂ (g) + 3H₂(g) $\rightleftharpoons$2NH₃ (g) + heat

 the equilibrium shifts in forward direction                                   

(1) by increasing the concentration of NH₃ (g) 

(2) by decreasing the pressure

(3) by decreasing the concentrations of N₂ (g)and H₂(g)

(4) by increasing pressure and decreassing temperature

Which is the strongest acid in the following?          

(a) H₂SO₄            (b) HClO₃        (c) HClO₄         (d) H₂SO₃ 

Find the conjugate acid of NH₂⁻.

1. NH₄⁺
2. NH₃
3. NH₂OH
4. N₂H₄

A 50 ml solution of strong acid of pH = 1 is mixed with a 50 ml solution of strong acid of pH=2. The pH of the mixture will be nearly:                                                     

(log 5.5 = 0.74)

1. 0.74                   2. 1.26

3. 1.76                   4.  1.5