Question

State True or False.

The polarising power of a cation is directly proportional to its size.

• A. True
• B. False

Answer 1

The correct option is B False

The polarizing power of a cation is inversely proportional to its size. Smaller is the size of the cation, higher will be its charge density (greater concentration of charge on a small area) and higher will be its polarising power. For example, the decreasing order of the polarising power of the cations is $L{i}^{+}>N{a}^{+}>K^{+}>R{b}^{+}>C{s}^{+}$. Thus, among the alkali metal cations, lithium ion has smallest size and highest polarising power.