Transition metal compound are coloured due to `d-d` and charge transfer tranditoins, Colour due to `d-d` transition is shown by transition metal compounds having `d^(1) and d^(9)` electrons whereas the compounds containing `d^(0) and d^(10)` configurations are intensely coloured due to charge transfer transitions.
Which of the following compound is not coloured

Options

A. ` Na_2CdCl_2`
B. Pressure of the reaction
C. Nature of ligands or Lewis bases attached to the metal ion
D. Concentration of the ligands

Answer

A

Explanation

Colour of the compounds of the same transition metal ion depends upon the nature of ligands attached to it. For example, `[CuCl_(4)]^(2-)` is greenish yellow, `[Cu(H_(2)O)_(4)]^(2+)` is blue but `[Cu(NH_(3))_(4)]^(2+)` is violet or deep blue.