Which cation forms a colorless aqueous solution?
(A) Co2+ (B) Ni2+ (C) Cu2+ (D) Zn2+
please explain
1 Answer
The Zn2+ ion has all the d electrons paired since it has an electron
configuration of [Ar]3d10. All of the other ions have unpaired d electrons which can absorb energy in the visible region and be promoted to a higher energy state.