Question

The highest reducing power in aqueous medium of lithium among other alkali metals is due to:

• A. very small size of lithium atom
• B. very low sublimation energy of lithium
• C. the lowest ionization energy of lithium among alkali metals
• D. very high hydration energy of $L{i}^{+}$ ion

Answer 1

Answer: (A), (D)

The correct options are
A very small size of lithium atom
D very high hydration energy of $L{i}^{+}$ ion

All the alkali metals have almost equal sublimation energy. Lithium has the highest ionization energy and hydration energy due to its small size. All three energies (sublimation, ionization and hydration) contribute to the oxidation potential.

For lithium, the hydration energy compensates the ionization energy. Hence among the alkali metals, lithium has the highest oxidation potential and the highest reducing power in the aqueous solution.

Hence, option A and D are correct.