When NH₄Cl is added to an aqueous solution of NH₄OH, then

1. Concentration of $\left[{\mathrm{OH}}^{-}\right]$ ions decreases.

2. Concentration of $\left[{\mathrm{OH}}^{-}\right]$ ions increases.

3. Concentration of $\left[{\mathrm{NH}}_4^{+}\right]$ ions as well as concentration $\left[{\mathrm{OH}}^{-}\right]$ ions increase.

4. Concentration of $\left[{\mathrm{NH}}_4^{+}\right]$ ions decreases.

The solubility of $\mathrm{Ni}{\left(\mathrm{OH}\right)}_2$ in 0.1 M NaOH is:

K_sp ($\mathrm{Ni}{\left(\mathrm{OH}\right)}_2$)= 2x ${10}^{-15}$

1. 2 x ${10}^{-8}$ M.

2. 1 x ${10}^{-13}$ M

3. 1 x ${10}^8$ M 

4. 2 x ${10}^{-13}$ 

The pH of a solution made by mixing 50 mL of 0.01 M barium hydroxide solution with 50 mL of H₂O is

The pK_a of HCN is 9.30. The pH of a solution prepared by mixing 2.5 moles of KCN and 2.5 moles of HCN in water and making up the total volume to 500 ml will be:

The basic buffer solution among the following is: 

1. ${\mathrm{NH}}_4\mathrm{Cl}+{\mathrm{NH}}_4\mathrm{OH}$

2. $\mathrm{NaCl}+\mathrm{NaOH}$

3. ${\mathrm{NH}}_4\mathrm{Cl}+{\mathrm{CH}}_3\mathrm{COOH}$

4. ${\mathrm{CH}}_3\mathrm{COONa}+{\mathrm{CH}}_3\mathrm{COOH}$

An acid buffer solution can be prepared by mixing the solutions of:

1. Sodium chloride and sodium hydroxide

2. Sulphuric acid and sodium sulphate

3. Ammonium chloride and ammonium nitrate

4. Ammonium acetate and acetic acid

Reaction quotient for the reaction, ${\mathrm{N}}_2\left(\mathrm{g}\right)+3{\mathrm{H}}_2\left(\mathrm{g}\right)\rightleftharpoons 2{\mathrm{NH}}_3\left(\mathrm{g}\right)$ is given by , $\mathrm{Q}$ $=$ $\frac{{\left[{\mathrm{NH}}_3\right]}^2}{\left[{\mathrm{N}}_2\right]{\left[{\mathrm{H}}_2\right]}^3}$ .The reaction will proceed from right to left if K_c value is:

The K_sp of Ag₂CrO₄ and AgBr is 1.1 × 10^–12 and 5.0 × 10^–13 respectively.

The molarity ratio of saturated solutions of Ag₂CrO₄ and AgBr will be:

The minimum volume of water required to dissolve 1g of calcium sulphate at 298 K is

(For CaSO₄ , K_sp is 9.1 × 10^–6)

1. 1.22 L

2. 0.69 L

3. 2.44 L

4. 1.87 L

The concentration of $\left[{\mathrm{H}}^{+}\right]$ ion in a solution containing 0.1 M HCN and 0.2 M NaCN will be:

(${\mathrm{K}}_{\mathrm{a}}$ for HCN = $6.2\times {10}^{-10}$)

1. 3.1$\times {10}^{10}$

2. $6.2\times {10}^5$

3.$$ $6.2\times {10}^{-10}$

4. $3.1\times {10}^{-10}$