b. 1 H, 7 N, 20Ca, 16S, 4 Be, 18Ar Which of these elements belong to the second group?

Question

Write down the electronic configuration of the following elements from the given atomic numbers. Answer the following question with explanation.

b. ₁H, ₇N, ₂₀Ca, ₁₆S, ₄ Be, ₁₈Ar Which of these elements belong to the second group?

Answer 1

 ₁H, ₇N, ₂₀Ca, ₁₆S, ₄ Be, ₁₈Ar 

Electronic configuration of atoms ::

 ₁H=1

 ₇N=2,5

 ₂₀Ca=2,8,8,2

 ₁₆S=2,8,6

 ₄ Be=2,2

 ₁₈Ar=2,8,8 

Among the given elements, Ca and Be belong to second group. Because both has two electrons in the outermost shell. Thus, these two elements belong to second group.