The energy of `sigma_(2s)`, is greater than that of `sigma_(1s)^**` orbital because

Options

A. `sigma_(2s)` is planar while `sigma_(1s)^**` is is non-planar etrical
B. `sigma_(2s)` is symmetrical while `sigma_(1s)^**` is unsymmetrical
C. `sigma_(2s)` is nearer to the nuclei than `sigma_(1s)^**`
D. none of these.

Answer

D

Explanation

The correct reason is as follows . The `sigma_(2s)` orbital originates from atomic orbitals of higher energy than itself and so is bonding. The `sigma_(1s)^**` originates from atomic orbitals of lower energy than itself and so it antibonding