Question

Assertion :

$NC{l}_3$ undergoes hydrolysis.

Reason: Chlorine possesses vacant d-orbitals.

• 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

The nitrogen in $NC{l}_3$ is often considered to have the 3 oxidation state and the chlorine atoms are considered to be in the +1 oxidation state.
It is hydrolyzed by hot water to release ammonia and hypochlorous acid.
$NC{l}_3+3H_{2}O\to N{H}_3+3HOCl$

Nitrogen (atomic weight 7) can combine with three chlorine ($Cl$) atoms, forming nitrogen trichloride, or $NC{l}_3$ . Nitrogen shares its electrons with the chlorine atoms, so all of the atoms have their shells filled. The $N-Cl$ bonds are therefore largely unpolarised and attack on the nitrogen by the oxygen atoms of water is therefore not favoured. Moreover, the lack of available d-orbitals in nitrogen makes its acceptance of lone pairs from attacking water molecules even less likely.

Thus chlorine possesses vacant d' orbitals with respect to filling their shell and also $NC{I}_3$ undergoes hydrolysis.

Option $A$ is correct.