Question

Which of the following alkali metal ions has lowest ionic mobility in aqueous solution.

• A. $Rb^{+}$
• B. $Cs^{+}$
• C. $Li^{+}$
• D. $Na^{+}$

Answer 1

Answer: (B)

$Cs^{+}$

Answer 2

Mobility decreases from top to bottom because of the atomic size is increases.