Oxidation of primary alcohols to aldehydes/carboxylic acids

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Created by
Sophie Grainger

Cards (10)

  • When a primary alcohol is oxidised, it forms an aldehyde.
  • Unlike ketones, aldehydes are more easily oxidised, so the aldehyde formed may be oxidised further. This will form a carboxylic acid.
  • The functional group of an aldehyde is R-C=O-H.
  • The functional group of a carboxylic acid is R-C=O-O-H.
  • The reagent for oxidation reactions is a mixture of potassium dichromate (VI) and dilute sulfuric acid.
  • [O] represents the oxygen atom provided by the oxidising agent in equations, and usually the actually formula for the oxidising agent isn't included in the equation.
  • When an oxidising agent is used, there is a colour change from orange to green.
  • An example of a primary alcohol being oxidised to an aldehyde is propan-1-ol being oxidised to propanal. The symbol equation for this reaction is CH3CH2CH2OH + [O] -> CH3CH2CHO + H2O.
  • An example of an aldehyde being further oxidised to a carboxylic acid is propanal being oxidised to propanoic acid. The symbol equation for this reaction is CH3CH2CHO + [O] -> CH3CH2COOH.
  • An example of a secondary alcohol being oxidised to a ketone is propan-2-ol being oxidised to propanone. The symbol equation for this reaction is CH3CH(OH)CH3 + [O] -> CH3COCH3 + H2O.