Question

Which of the following sequences represents the increasing order of the polarizing power of the cationic species?

• A. $M{g}^{2+}<B{e}^{2+}<K^{+}<C{a}^{2+}$
• B. $B{e}^{2+}<K^{+}<M{g}^{2+}<C{a}^{2+}$
• C. $C{a}^{2+}<K^{+}<B{e}^{2+}<M{g}^{2+}$
• D. $K^{+}<C{a}^{2+}<M{g}^{2+}<B{e}^{2+}$

Answer 1

The correct option is D $K^{+}<C{a}^{2+}<M{g}^{2+}<B{e}^{2+}$

Polarising power is the ability of cation to indicate how strongly it can pull the anion's electron.
High charge and small charge of the cation increases the polarization power
Order of the radius of cations is: $K^{+}>C{a}^{2+}>M{g}^{2+}>B{e}^{2+}$
So, order of increasing polarization power is: $K^{+}<C{a}^{2+}<M{g}^{2+}<B{e}^{2+}$