Question

What is the electron configuration of an element with atomic number 9?

Answer 1

`1s^2 2s^2 2p^5`

Explanation:

Atomic number 9 is the element Florine

Florine has 9 electrons as well as the 9 protons that determine its atomic number.

The ground state configuration is the lowest energy configuration.

so `1s^2 2s^2 2p^5`