Reactions

• Carboxylic acids


  Acidic substances that contain the -COOH group
• Why carboxylic acids are acidic


  1. Hydrogen in the -COOH group transfers to water molecule

  2. Reversible reaction

  3. Weak acid
• Carboxylic acids reacting with metals

  1. Produce salt and hydrogen gas

  2. Slower reaction than with HCl
• Carboxylic acids reacting with metal hydroxides

  1. Neutralisation reaction

  2. Produce salt
• Carboxylic acids reacting with carbonates and hydrogencarbonates

  Produce salt, carbon dioxide and water
• Carboxylic acids reacting with ammonia


  Produce ammonium salt
• Carboxylic acids reacting with amines


  Produce amine salt
• Esters

  Compounds where the hydrogen in the -COOH group of a carboxylic acid is replaced by a hydrocarbon group
• Making esters

  1. Heat carboxylic acid and alcohol with acid catalyst

  2. Reversible reaction
• Converting carboxylic acids to acyl chlorides


  1. Replace -OH with -Cl using PCl5, PCl3 or SOCl2

  2. Acyl chlorides are very reactive
• Decarboxylation of carboxylic acids and their salts

  1. Heat solid sodium salt with soda lime

  2. Removes -COOH or -COONa group and replaces with H
• Soda lime


  • Mixture of NaOH, CaO and Ca(OH)2
  • Easier to handle than solid NaOH
• Decarboxylation can be done with certain carboxylic acids themselves, e.g. heating benzoic acid with soda lime produces benzene