Question

How to determine valence electrons through electron configuration?

Answer 1

Let's take the electron nitrogen

It's atomic number is 7.

K,l

Nitrogen (N) - 2,5.

( Electronic

configurationn )

There are 5 electrons in the outermost shell.

There can be only 2 electrons in the first shell (K)

It has to loose either 3 electrons to become duplet (2) Or gain 3 electrons to become octet (8).

Therefore the valence electron can be either 3 if it lose or -3 if it gains.

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