Question

The addition of ammonium chloride to 0.1 M acetic acid will cause:

• A. increase in its pH value
• B. decrease in its pH value
• C. no change in pH value
• D. change in pH which cannot be predicted

Answer 1

The correct option is B

decrease in its pH value

Acid will furnish $H^{+}$ ions.
$N{H}_{4}Cl$(aq) + $H_{2}O$ (l) $\leftrightharpoons$ $N{H}_{4}OH$ (aq) + $H^{+}$ (aq)

Salt of (Weak base + Strong acid) on hydrolysis will also furnish $H^{+}$. Hence pH decreases