Question

The ionic mobility of alkali metal ions in aqueous solution is maximum for

• A. $K^{+}$
• B. $R{b}^{+}$
• C. $L{i}^{+}$
• D. $N{a}^{+}$

Answer 1

Answer: (B)

Smaller the size of the ion, more highly it is hydrated and hence, its hydrated ionic radius will be greater and its ionic mobility is lesser in aqueous solution. Thus, the order of ionic mobility is $L{i}^{+}<N{a}^{+}<K^{+}<R{b}^{+}<C{s}^{+}$