Which of the following is most soluble in water?

1. MnS (K_sp = 8x10^-37)       

2. ZnS (K_sp = 7x10^-16)

3. Bi₂S₃ (K_sp = 1x10^-70)       

4. Ag₂S (K_sp = 6x10^-51)

The compound that does not act as Lewis acid is:

1. AlCl₃                                             

2. BF₃

3. NH₃                                             

4. FeCl₃

The values of K_p1 and K_p2 for the reactions

$\mathrm{X}\rightleftharpoons \mathrm{Y} + \mathrm{Z} ........\left(\mathrm{i}\right)$
$\mathrm{and} \mathrm{A}\rightleftharpoons 2\mathrm{B} .........\left(\mathrm{ii}\right)$

are in ratio of 9:1, if degree of dissociation of X and A be equal, then total pressure at equilibrium (i) and (ii) are in the ratio 

(a) 3:1

(b) 1:9

(c) 36:1

(d) 1:1

For NH₄HS(s) $\rightleftharpoons$NH₃ (g) + H₂S(g), the observed pressure for reaction mixture in equilibrium is 1.12 atm at 106$°$C. The value of K_p for the reaction is:

(1) 3.136 atm²                           

(2) 0.3136 atm²

(3) 31.36 atm²                           

(4) 6.98 atm²

The relation for calculating pH of a solution containing weak acid and its salt is:

(1) pH = pK_a + log$\frac{[\mathrm{Conjugate} \mathrm{Base}]}{\left[\mathrm{Acid}\right]}$

(2) pH = pK_a - log$\frac{[\mathrm{Conjugate} \mathrm{Base}]}{\left[\mathrm{Acid}\right]}$

(3) pH = pK_a + log$\frac{[\mathrm{Conjugate} \mathrm{Base}]}{\left[\mathrm{Salt}\right]}$

(4) pOH = pK_a - log$\frac{\left[\mathrm{Acid}\right]}{[\mathrm{Conjugate} \mathrm{Base}]}$

Solubility of a gas in liquid increases on:

(1) addition of a catalyst

(2) increasing the pressure

(3) decreasing the pressure

(4) increasing the temperature

Which of these is least likely to act as a Lewis base?             

(1) CO         

(2) F^-           

(3) BF₃         

(4) PF₃

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

(a) 5.65 x 10^-10                      (b) 6.50 x 10^-12

(c) 5.65 x 10^-13                      (d) 5.65 x 10^-12

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

The stronger Bronsted based is:

(a) ClO^-                (b) Cl${\mathrm{O}}_2^{-}$   

(c) Cl${\mathrm{O}}_3^{-}$               (d)  Cl${\mathrm{O}}_4^{-}$