AP EAPCET 20-Aug-2021 Shift 1 Paper

The electronic configuration of Cu2+ is [Ar]3d9
It contains one unpaired electron,
Hence, CuCl2 is coloured compound.
In all other compounds,
CuCl→[Cu+]⇒3d104s0
ScCl3→[Sc3+]⇒3p64s2
TiCl4→[Ti4+]⇒3p64s2
No unpaired electrons are present.