Preparation of Aldehydes and Ketones

Aldehydes can be prepared from the oxidation of primary alcohols using potassium dichromate VI acidified with sulfuric acid. The aldehyde has a relatively low boiling point and can be distilled off as it is formed.Ketones can be prepared by refluxing secondary alcohols with acidified potassium dichromate VI.The dichromate VI ion is reduced to the Cr³⁺ ion.Cr₂O₇^2- + 14 H⁺ + 6e^- → 2Cr³⁺ + 7H₂O