Question

Which of the following has the largest radius?

ОА. К
O B. K+
O C. Na
O D. Na+

Answer 1

A. K

Step-by-step explanation:

Radius of an atom is directly propotional to number of shells. Potassium (K) has 4 shells (as it is in period 4) whlie sodium (Na) has 3 shells (as it is in period 3) therfore K > Na.

Cations are always smaller than their parent atoms. so increasing order is

Na+ < Na < K+ < K