f. 19K, 3 Li, 11Na, 4 Be Which of these atoms has smallest atomic radius?

Question

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

f. ₁₉K, ₃Li, ₁₁Na, ₄Be Which of these atoms has smallest atomic radius?

Answer 1

₁₉K, ₃Li, ₁₁Na, ₄Be

elements and thier electronic configuration:

₁₉K=2,8,8,1

 ₃Li=2,1

 ₁₁Na=2,8,1

 ₄Be=2,2

The element with the smallest atomic radius is ₄Be because atomic size decreases moving across a period from left to the right while it increases down a group.