Question
$\ce{CuSO_4​⋅5H_2O}$ is blue is colour while $\ce{CuSO_4}$​ is colourless due to$:$

Answer

In $\ce{CuSO_4​⋅5H_{2​}O},$ water acts as ligand and causes crystal filed splitting.
This makes $d - d$ transitions possible.
On the other hand, in $\ce{CuSO_4​},$ due to absence of ligand crystal filed splitting is not possible.
Hence no colour is observed.

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free