Question

Determine the number of valence electrons in each of the following elements.
(Express your answer as an integer)

A. Ba

B. Hf

C. Ni

D. S

Answer 1

A. Ba = [Xe] 6s2
2 valence e

B. Hf = [Xe] 4f14 5d2 6s2
2 valence e

C. Ni = [Ar] 3d8 4s2
2 valence e

D. S = [Ne]3s2 3p4
6 valence e

Answer 2

Ba = 2 ; second group in the periodic table
Ni = 10 ; 10th group, follows regular rules
HF = 6 because it is 1 from hydrogen and 7 from fluorine but because bond takes 2
it goes from 8 total to 6.
S = 6 due to 6 group .

Answer 3

A.) Ba -- Total electrons = 56

[Xe]6s²

Valence electron = 2

B.) Hf -- Total electrons = 72

[Xe] 4f¹⁴5d⁴6s²

Valence electron = 2

C.) Ni -- Total electrons = 28

[Ar]3d⁸4s²

Valence electron = 2

D.) S -- Total electrons = 16

[Ne]3s²3p⁴

Valence electrons = 6