Question

A sodium atom has an electron configuration of `1s^2 2s^2 2p^6 3s^1`. If the sodium atom becomes ionized, its new electron configuration will be the same as which element?

Answer 1

Neon.

Explanation:

If the sodium is ionised, the outer `3s^1` electron is lost, so the configuration becomes

`1s^2 2s^2 2p^6`,

which is the same as neon, `Ne`.