Question

Which of these elements has two valence electrons? A. hydrogen (H) B. barium (Ba) C. nitrogen (N) D. krypton (Kr) E. bromine (Br)

Answer 1

Barium has two valence electrons

Answer 2

So whenever you need to find valence electron look at Group Number and you can find it, Example barium it’s on group 2 it’s means it have 2 valence electrons.
let’s look for nitrogen group 5A that means it have 5 valence eletrons.
hope it’s help.
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