Question

Trimethyl amine is pyramidal but trisilyl amine is planar why ?​

Answer 1

Answer:

Explanation:

This is due to backbonding of the lonepair on nitrogen to silicon's empty d-orbital. Hence due to this backbonding the geomery changes to planar geometry.( the back bonding is due to the electron afffinty of SI towards N's lone pair.)

Whereas for triethyl amine....carbon does not have an empty d-orbital to attract nitrogen's lone pair. Hence its geometry remains pyramidal.