The correct basicity order of the following lanthanide ions is -

Options

A. `La^(3)gt Lu^(3+)gt Ce^(3+)gt Eu^(3+)`
B. `Ce^(3+)gt Lu^(3+)gt La^(3+)gt Eu^(3+)`
C. `Lu^(3+)gt Ce^(3+)gt Eu^(3+)gt La^(3+)`
D. `La^(3+)gt Ce^(3+)gt Eu^(3+)gt Lu^(3+)`

Answer

D

Explanation

From `La^(3+)` to `Lu^(3+)` the radii of the lanthanide cations gradually decreases. Thus their covalent character decreases and hence basicity also decreases.