question_answer

Cuprous ion is colourless while cupric ion is coloured because

A)  both have half-filled p and d-orbital

B)  cuprous ion has completed d-orbital and cupric ion has incomplete d-orbital

C)   cuprous ion has incomplete d-orbital and cupric ion has complete d-orbital

D)  both have unpaired electrons in d-orbital

Correct Answer: B

Solution :

                 Cuprous ion has completed d-orbital\[(3{{d}^{10}})\] hence it is colourless, while cupric ion has incomplete d-orbital \[(3{{d}^{9}})\] and therefore, it is coloured.            Cuprous ion\[(3{{d}^{10}}):\]     Cupric ion \[(3{{d}^{9}}):\]