Question

Assertion :$N(C{H}_3{)}_3$ is pyramidal but $N(Si{H}_3{)}_3$ is planar. Reason: In $N(Si{H}_3{)}_3$ lone-pair on $N-$atom is transferred to the empty $d-$ orbitals of silicon $(p\pi -d\pi$ overlapping).

• 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.

$N(C{H}_3{)}_3$ is pyramidal but $N(Si{H}_3{)}_3$ is planar because in $N(Si{H}_3{)}_3$ lone-pair on $N-$atom is transferred to the empty $d-$ orbitals of silicon $(p\pi -d\pi$ overlapping) and there is no such possibility in case of $N(C{H}_3{)}_3$ due to absence of empty d-orbitals on C-atom.