Question

Assertion :The $pH$ of $N{H}_{4}Cl$ solution in water is less than $7$ and pH of $C{H}_{3}CCOONa$ solution is more than $7$. Reason: $N{H}_{4}Cl$ is a salt of weak base $N{H}_{4}OH$ and strong acid $HCl$ whereas $C{H}_{3}COONa$ is a salt of a weak acid $C{H}_{3}COOH$ and strong base $NaOH$.

• A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
• B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
• C. Assertion is correct but Reason is incorrect
• D. Both Assertion and Reason are incorrect

Answer 1

The correct option is A Both Assertion and Reason are correct and Reason is the correct explanation for Assertion

$N{H}_{4}Cl$ when is dissolved in water, it breaks into its constituent ions which are $N{H}_4^{+}$ & $C{l}^{-}$. Since, it is made up of a strong acid $HCl$ and a weak base $N{H}_{4}OH$. Therefore, overall it behaves as an acid on dissolution of water as it is made up of strong acid and acids have $pH$, less than $7$. Similarly, $C{H}_{3}COONa$ is made up of a weak acid, acetic acid $\left(C{H}_{3}COOH\right)$ and a strong base $NaOH$. Hence it behaves as a base salt in water & hence its $pH$ is greater than $7$.