Question

The charge/size ratio of a cation determines its polarizing power. Which one of the following sequences represents the increasing order of the polarizinig order of the polarizing power of the cationic species, $K^+, Ca^{2+}, Mg^{2+}, Be^{2+}$?

• A. $Mg^{2+} ,Be^{2+} ,K^{+} ,Ca^{2+}$
• B. $Be^{2+} ,K^{+} ,Ca^{2+} ,Mg^{2+}$
• C. $K^{+} ,Ca^{2+} ,Mg^{2+} ,Be^{2+}$
• D. $Ca^{2+} ,Mg^{2+} ,Be^{2+} ,K^{+}$

Answer 1

Answer: (C)

Higher the charge/size ratio, more is the polarizing power.
$\therefore K^{+} ,Ca^{2+} ,Mg^{2+} ,Be^{2+}$