Question

write how many valence electrons in a)Na atom and ion b) O atom and ion

Answer 1

Valence electrons in
a) Na atom is 1 ( electronic configuration= 2,8,1 )
Na ion is 8 because it loses 1 electron.
b) O atom is 6 ( electronic configuration= 2,6)
O ion is 8 because it gains 2 electrons.

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