Reaction Summary
Reagents
- Acidified potassium dichromate(VI),
/ dilute - or acidified potassium manganate(VII),
/ dilute
Conditions
- Heat under reflux
Catalyst
- None
Chemical Equation
Equation
By-Products
- None in the [O] equation (
/ from the oxidant)
Observations
Observations
- Orange ➔ green (
➔ ) - or purple ➔ colourless (
➔ )
⚠️ 9701 Exam Notes / Pitfalls
Warning
- Reflux (not distillation) keeps the volatile aldehyde in contact with the oxidant until fully oxidised.
- Ketones are not oxidised — the orange colour stays, so acidified dichromate distinguishes aldehydes from ketones.