Colours of Transition Metal Ions

 

Colours of Transition Metal Ions

·      Colour in transition metal ions depends upon presence of unpaired electron which show d-d transition of unpaired electron from t_2g to e_g set of energies when electron absorbs energy to jump from t_2g to e_g and come back to t_2g from e_g by emission of energy that appear with colour

Ex.:

 Ti⁺⁴, ------ [Ar] 3d⁰4s⁰ ----- no of unpaired electron ----->Zero---> colourless

 V⁺⁵ -----[Ar] 3d⁰4s⁰ -----no of unpaired electron ----->Zero---> colourless

Ans - Because of absence due to presence of paired electrons which do not show d-d transition

Ex-

 Sc^2+, ---------[Ar] 3d¹4s⁰ ------no of unpaired electron ----->1e^- ---> coloured

Cr³⁺ ---------[Ar] 3d³4s⁰ ------no of unpaired electron ----->3e^- ---> coloured

Ans- due to presence of unpaired electrons which show d-d transition.