Question

Assertion :$Al(OH{)}_3$ is insoluble in $N{H}_{4}OH$ but soluble in $NaOH$. Reason: $NaOH$ is strong alkali.

• A. Both assertion and reason are true and the reason is a correct explanation of the assertion
• B. Both assertion and reason are true but reason is not a correct explanation of the assertion
• C. The assertion is true but reason is false
• D. The assertion and reason are false

Answer 1

The correct option is A Both assertion and reason are true and the reason is a correct explanation of the assertion

Assertion
$Al(OH{)}_3$ is insoluble in $N{H}_{4}OH$ but soluble in $NaOH$.
Reason

$NaOH$ is strong alkali. In presence of excess $NaOH$, $Al(OH{)}_3$ forms sodium meta aluminate which is soluble.
$Al(OH{)}_3+NaOH\to Na[Al{O}_2]+2H_{2}O$
Thus both assertion and reason are true and the reason is a correct explanation of the assertion.