Question

Assertion :Ammonia is a base. Reason: Ammonia when dissolved in water takes up proton to form ammonium and furnishes $O{H}^{-}$ ions.

• 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

In aqueous solution, ammonia deprotonates a small fraction of the water to give ammonium and hydroxide according to the following equillibirium:

$N{H}_3$ + $H_{2}O$ $\rightleftharpoons$ $N{H}_4^{+}$ + $O{H}^{-}$ .

In a $1M$ ammonia solution, about $0.42$ of the ammonia is converted to ammonium, equivalent to a $pH$ of $11.63$.

Thus, option $A$ is correct because both assertion and reason are correct and the reason is the correct explanation of the assertion.