Question

Write the valence electrons in A)Na atom and Na+ ion B) O atom and O-2 ion

Answer 1

Valance electron in

1 ) Na = 1 ( 2,8,1 )
2 ) Na+ = 8 ( 2,8 ) because it loses 1
3 ) O = 6 ( 2,6 )
4 ) O-2 = 8 ( 2,8 ) because it gains 2

Answer 2

Na atom 2,8,1
Na+ ion 2,8
O atom 2,6