Preparing Carboxylic Acids
Making Carboxylic Acids by Oxidising Primary Alcohols
- Alcohols can be oxidised to carboxylic acids using potassium dichromate(VI) solution in the presence of dilute sulphuric acid.
- Chemical Equation below represents the reaction.
C2H5OH+2[O] → CH3COOH + H2O
- The figure below shows the apparatus set up to prepare ethanoic acid.
- The mixture is heated under reflux to prevent the ethanol to evaporate and escape to the surrounding before it has time to be oxidised to the carboxylic acid.
- Ethanol vapour will condense into liquid in the Liebig condenser and flow back into the flask to complete the reaction.
- The mixture is heated by using a water bath:
- to keep the temperature constant
- to ensure a uniform heating (heat is evenly supplied)