Question

Which of the following statements is not correct?
A. `La(OH)_(3)` is less basic than `Li(OH)_(3)`
B. In lanthanide series, ionic radius of `Ln^(3+)` ion decreases
C. La is actually an element of transition series rather lanthanide
D. Atomic radius of Zr and Hf are same because of lanthanide contraction.

Answer 1

Correct Answer - A
`La^(3+)` ions larger than `Li^(3+)`. So, it easily gives `OH^(-)` ion La `(OH)_(3)` is more basic than `Li(OH)_(3)`. In lanthanides the basic character of hydroxides decreases as the ionic radius decreases.