Question

What does having 8 valence electrons mean about Noble Gases?

Answer 1

Valence electrons are the electrons present in the outermost shell of an atom.

All noble gases (except He- has 2) have 8 electrons in the outermost shell.

Eg- neon (atomic number 10) has electronic configuration 1s2 2s2 2p6

The outermost shell in this case is 2 which has total of 2+6=8 electrons

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