Consider the following statement in respect of Lantinanoids :
(i) The basic strength of hydroxides of lanthanoids increases from `La (OH)_(3)` to `Lu (OH)_(3)`.
(ii) The lanthanoid ions `Lu^(3+), Yb^(2+)` and `Ce^(4+)` are diamagnetic.
Which of the statements (s) given above is /are correct ?

Options

A. (i) only
B. (ii) only
C. Both (i) and (ii)
D. Neither (i) nor (ii)

Answer

B

Explanation

(i) basic strength decrease from `La (OH)` to `Lu (OH)_(3)` because moving from left to right `Z_("eff")` increases so size of `M^(+3)` cation decreases, covalent character increases so basic strength decreases between `M^(+3)` and `OH^(-)` ion.
(ii) `Lu^(3+) . Yb^(2+)` have `f^(14)` electronic configuration and `Ce^(4+)` has `f^(0)` electronic configuration so they are diamagnetic.