Question

explain why 2s electron has a lower energy than a 2p electron​

Answer 1

Explanation:

In atoms with more than one electron, 2s is lower in energy than 2p. An electron in a 2s orbital is less well shielded by the other electrons than an electron in a 2p orbital. (Equivalently, the 2s orbital is more penetrating.) The 2s electron experiences a higher nuclear charge and drops to lower energy.

Answer 2

Explanation:

In atoms with more than one electron, 2s is lower in energy than 2p. An electron in a 2s orbital is less well shielded by the other electrons than an electron in a 2p orbital. (Equivalently, the 2s orbital is more penetrating.) The 2s electron experiences a higher nuclear charge and drops to lower energy.