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Q.
The colour of transition metal compound is due to
J & K CETJ & K CET 2014The d-and f-Block Elements
Solution:
Most of the compounds of transition metals are coloured in solid state or solution. This is due to their incomplete $ (n-1) $ $ d- $ subshell. Their colour arises from the excitation of electron from d-orbitals of lower energy to $ d- $ orbitals of higher energy (i.e., $d-d$ transition).