The species `Ar,K^(+)` and `Ca^(2+)` contain the same number of electrons. In which order do their radii increase ?

Options

A. `Ca^(2+)lt K^(+)lt Ar`
B. `K^(+)lt Ar lt Ca^(2+)`
C. `Ar lt K^(+)lt Ca^(2+)`
D. `Ca^(2+)lt Ar lt K^(+)`

Answer

A

Explanation

Atomic radius and ionic radius `prop (1)/(Z_("effective"))`