Question

Why we not calculate the electron kinetic energy when it is far from nucleus

Answer 1

Explanation:

When electrons are excited they move to a higher energy orbital farther away from the atom. The further the orbital is from the nucleus, the higher the potential energy of an electron at that energy level. When the electron returns to a low energy state, it releases the potential energy in the form of kinetic energy.

Answer 2

Explanation:

Electrons relatively far away have smaller and so this energy term is less negative