Edexcel IAL Chemistry A2 17.21 chromate(VI) and dichromate(VI) equilibrium
Edexcel IAL Chemistry A2 17.21 chromate(VI) and dichromate(VI) equilibrium
Use the equilibrium equation to explain the colour: alkali removes H+ and favours yellow chromate(VI), while acid favours orange dichromate(VI).
How this is tested
- Explain alkaline shift to chromate(VI) by removal of H+ from equilibrium.
- Write 2CrO4^2- plus 2H+ forming Cr2O7^2- and water for acidification equations.
- Identify yellow chromate(VI), orange dichromate(VI) and green chromium(III) species.