Which of the following complexions is expected to absorb visible light ? (Al. No. Zn=30, SC=21, Ti= 22, Cr= 24)

Options

A. `[Ti(en)_(2)(NH_(3))_(2)]^(4+)`
B. `[Cr(NH_(3))_(6)]^(3+)`
C. `[Zn(NH_(3))_(6)]^(2+)`
D. `[Sc(H_(2)O)_(3)(NH_(3))_(3)]^(3+)`

Answer

B

Explanation

`d^(0)(Ti^(4+), Sc^(3+))` and `d^(10)(Zn^(2+))` species will not absorb visible light and are colourless whereas `d^(3)(Cr^(3+))` can undergo d-d transition on absorption of visible light of a particular wavelength and will be coloured.