100 mL of 0.01 M solution of NaOH is diluted to 1 dm³. What is the pH of the diluted solution?

• 12

• 11

• 2

• 3

512.

Relation between hydrolysis constant and dissociation constant are given. Which is the correct formula for MgCl₂ ?

• K_h = $\frac{{\mathrm{K}}_{\mathrm{w}}}{{\mathrm{K}}_{\mathrm{a}}}$

• K_h = $\frac{{\mathrm{K}}_{\mathrm{w}}}{{\mathrm{K}}_{\mathrm{b}}}$

• K_h = $\frac{{\mathrm{K}}_{\mathrm{w}}}{{\mathrm{K}}_{\mathrm{a} }\times {\mathrm{K}}_{\mathrm{b}}}$

• K_w = $\frac{{\mathrm{K}}_{\mathrm{h}}}{{\mathrm{K}}_{\mathrm{b}}}$

Calculate pOH of 0.001 M NH₄OH when it is 1% dissociated in the solution.

• 5

• 2.96

• 9.04

• 11.04

The values of dissociation constant of bases are given below. Which is the weakest base?

• 1.8 × 10^-5

• 4.8 × 10^-10

• 7.2 × 10^-11

• 7.07 × 10^-7

The pH of millimolar HCl is

• 1

• 3

• 2

• 4

0.5 M ammonium benzoate is hydrolysed to 0.25 percent, hence, its hydrolysis constant is

• 2.5 x 10^-5

• 1.5 x 10^-4

• 3.125 x 10^-6

• 6.25 x 10^-6

Conjugate base of ${\mathrm{HSO}}_4^{-}$ is

• ${\mathrm{SO}}_4^{2-}$

• H₂SO₄

• ${\mathrm{H}}_3{\mathrm{SO}}_4^{+}$

• None of these

The pK_a of a weak acid is 4.8. What should be the ratio of $\frac{\left[\mathrm{acid}\right]}{\left[\mathrm{salt}\right]}$, if a buffer of pH = 5.8 is required?

• 0.1

• 10

• 1

• 2

Which of the following would produce a buffer solution when mixed in equal volumes?

• 1 M CH₃COOH and 0.5 M NaOH

• 1 M CH₃COOH and 0.5 M HCl

• 1 M NH₄OH and 0.5 M NaOH

• 1 M NH₄Cl and 0.5 M HCl

Equilibrium constant for the reaction,

H₂O (g) + CO (g) $\rightleftharpoons$H₂ (g) + CO₂ (g) is 81.

If velocity constant of the forward reaction is 162 L mol^-1s^-1. What is the velocity constant (in L mol^-1s^-1) for the backward reaction?

• 13122

• 2

• 261

• 243