ChemistryCode 9701
Carboxylic acids
What this topic asks you to be able to do
- recall how benzoic acid can be made, namely by heating an alkylbenzene with alkaline KMnO₄ and subsequently treating the mixture with dilute acid, using methylbenzene as the example
- describe what happens when carboxylic acids are treated with PCl₃ and heated, or with PCl₅ or SOCl₂, to yield acyl chlorides
- recognise that certain carboxylic acids may undergo further oxidation: methanoic acid, HCOOH, is oxidised to carbon dioxide and water by Fehling's reagent, Tollens' reagent, acidified KMnO₄ or acidified K₂Cr₂O₇, while ethanedioic acid, HOOCCOOH, is oxidised to carbon dioxide by warm acidified KMnO₄
- outline and account for how the acidities of carboxylic acids, phenols and alcohols rank against one another
- describe and explain how chlorine-substituted carboxylic acids compare in acidity