Question

Chromate ion is yellow in colour but dichromate ion is orange in colour thiugh bith have +6 oxidation state

Answer 1

1. The colour of CrO₄^2- is yellow while Cr₂O₇^2- is orange but the two have Cr in +6 oxidation states.

2. This happens because, the structure of dichromate has one bridging oxygen, which has a higher imapct on spilting, distinguishes the charge transfer of both.

3. Thus, dichromate ion absorbs in high energy region, thus radiate colour of low energy.