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${\mathrm{O}}_4^{-}$ 

The equilibrium, 2SO₂ (g) + O₂ (g) $\rightleftharpoons$2SO₃ (g)

shifts forward if:

(1) a catalyst is used

(2) an absorbent is used to remove SO₃ as soon as it is formed

(3) small amounts of reactants are used

(4) none of the above

The pH of blood is maintained by CO₂ by and H₂CO₃ in the body and chemical constituents of blood. This phenomenon is called:

(a) colloidal                            (b) buffer action

(c) acidic                                (d) salt balance

At temperature T, a compound AB₂ (g) dissociates according to the reaction 2AB₂$\rightleftharpoons$2AB(g) +B₂(g) with a degree of dissociation x, which is small compared with unity. The expression for K_p, in terms of x and the total pressure P , is:

(1) Px³/2

(2) Px²/3

(3) Px³/3

(4) Px²/2