In which of the following pairs, both the ions are coloured in aqueous solutions? (a) Sc3+, Ti (b) Sc3+, Co2+ (c) Ni2+, Cu+ (d) Ni2+, Ti3+ [Atomic no of Sc = 21, Ti = 22, Ni = 28, Co = 27, Cu = 29]

In which of the following pairs, both the ions are coloured in aqueous

1.	In which of the following pairs, both the ions are coloured in aqueous solutions? (a) Sc3+, Ti (b) Sc3+, Co2+ (c) Ni2+, Cu+ (d) Ni2+, Ti3+ [Atomic no of Sc = 21, Ti = 22, Ni = 28, Co = 27, Cu = 29]
Answer» Option (d) is the RIGHT answer Explanation:Due to presence of UNPAIRED d- orbital electrons. TI3+ has 1 d orbital ELECTRON and is purple in color. Ni2+ has 8 d orbital electron and has Green color.