question_answer 28)

 Predict which of the following will be coloured in aqueous solution? Ti3+, V3+,  Cu+, Sc3+, Mn2+ , Fe3+ and Co2+ Give reason for each.

Answer:

Ti3+ (3d1), Mn2+ (3d5), Fe3+ (3d5), Co2+ (3d8) ions are coloured in aqueous solutions. This due to the presence of partially filled d-subshell (or presence of unpaired electrons).