Which of the following statement(s) is/are true?

Options

A. In metal carbonyl complexes `d_(C-O)` increases compared to that in CO molecule
B. The pair of compounds `[Cr(H_(2)O)_(6)]Cl_(3) and [CrCl_(3)(H_(2)O)_(3)]*3H_(2)O` show hydrte isomerism
C. `d_(x^(2))` orbital of central metal atom/ion is used in `dsp^(2)` hybridisation
D. Facial and Meridonial isomers associated with `[Ma_(3)b_(3)]^(n+-)` type complex compound, both are optically inactive.

Answer

A, D

Explanation

`M underset(a)overset(pi)hArrL`, in metal carbonyl complexes `C-O` bond length increases compared to that in CO molecule as filled 'd' orbital of metal atom overlaps with `pi`-antibonding M.O. of CO `[CrCl_(3)(H_(2)O)_(3)].3H_(2)O` is not hydrate isomer of `[Cr(H_(2)O)_(6)]Cl_(3)`
Facial and meridional isomers of `[Ma_(3)b_(3)]^(n+)` complex are optically inactive as each one contains plane of symmetry.