Question

Which of the following compounds is expected to be colored?

• A. ${Ag}_2{SO}_4$
• B. $Cu{F}_2$
• C. $Mg{F}_2$
• D. $CuCl$

Answer 1

The correct option is B $Cu{F}_2$

If all the electrons are paired the element is not colored.

In $Cu{F}_2$ the oxidation state of Cu is +2.

Hence the electronic configuration is $4s^{0}3d^9$.

Partiallly filled d orbital is present in $C{u}^{2+}$

Therefore it is colored.