The charge/size ratio of a cation determines its polarizing power. Which one of the following sequences represents the increasing order of the polarizing power of the cationic species, `K^(+), Ca^(2+), Mg^(2+), Ba^(2+)`?

Options

A. `Ca^(2+) lt, Ca^(2+) lt Be^(2+) lt K^(+)`
B. `Mg^(2+) lt, Be^(2+) lt K^(+) lt Ca^(2+)`
C. `Be^(2+) lt, K^(+) lt Ca^(+) lt Mg^(2+)`
D. `K^(+) lt, Ca^(2+) lt Mg^(2+) lt Be^(2+)`

Answer

D

Explanation

The polarising power of cation increases with the increase n sharge/size ratio (i.e., grater the charge and smaller the size). Therefore, the correct increasing order of polarising power of the cation is :
`K^(+) lt Ca^(2+)ltMg^(2+)lt Be^(2+)`