Question

How many valance electrons do atoms in group 1 group 2 and groups 15 to 17 have?

Answer 1

Valence electrons is the number of electrons present in the outermost shell of an isolated gaseous atom.

Group 1 has one valence electrons.

Group 2 has two valence electrons.

Group 15 has  five valence electrons.

Group 16 has six valence electrons.

Group 17 has seven valence electrons.

The last digit indicates the number of valence electrons.

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