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

The species Ar, K^(+) " and " Ca^(2+) contain the same number of elect

1.	The species Ar, K^(+) " and " Ca^(2+) contain the same number of electrons. In which order do their radii increase ?
Answer» `Ca^(2+) lt AR lt K^(+)` `Ca^(2+) lt K^(+) lt Ar` `K^(+) lt Ar lt Ca^(2+)` `Ar lt K^(+) lt Ca^(2+)` Solution :`Ca^(2+) lt K^(+) lt Ar` `{:("Radius "alpha 1/(Z_("eff"))" for isoelectronic species "),(""Ca^(2+) ""K^(+) "Ar"),("Z201918"),(ul("No. of" BAR(E) "181818")),( leftarrow " Nuclear charge increses "leftarrow),(.:. to " Their redii increases" to ):}`