Question

What is the correct order of polarising power

• A. $M^{1+}<M^{2+}<M^{3+}<M^{4+}$
• B. $M^{1+}>M^{2+}>M^{3+}>M^{4+}$
• C. $M^{1+}<M^{2+}>M^{3+}<M^{4+}$
• D. $M^{4+}<M^{2+}<M^{3+}<M^{1+}$

Answer 1

The correct option is A $M^{1+}<M^{2+}<M^{3+}<M^{4+}$

According to Fajan’s Rule, a cation having more positive charge and a smaller size has greater polarising power, therefore the order of polarising power is $M^{+}<M^{2+}<M^{3+}<M^{4+}$.
(A) As the polarising power is increasing so is the order $M^{1+}<M^{2+}<M^{3+}<M^{4+}$