Carboxylic acids

Starter

Which of the following formulae represent carboxylic acids?

1. CH3CH2CH(CH3)COOH

2. (CH3)2CHCHO

3. CH3CH2OH

4. C6H5CH2COOH

Learning outcomes

• Recall the functional group of a carboxylic acid and an ester

• Describe the solubility of carboxylic acids

• Explain why they react like acids

• Apply the rules of naming an ester to naming esters

Carboxylic acids

A large number are found in nature, where they are often the cause of a sharp or sour taste

Ethanoic acid

2-Hydroxypropane-1,2,3-tricarboxylic acid

Butonic acid

2-hydroxybutanedioic acid

Methanoic acid

2-hydroxypropanoic cid

Bonding and acid reactions

• carboxylic bonding challenge.doc

• Carboxylic acids challenge2.doc

Esterification

• Reactants• Carboxylic acid and alcohol

• Conditions• Heat and concentrated H2SO4

Naming esters

• Propanoic acid + ethanol ethyl propanoate• __________ + methanol methyl pentanoate• Butanoic acid + butanol • __________ + _______ propyl methanoate

Naming esters

• Make three rules for naming esters

The alcohol stem comes at the start of the ester name;

The acid stem provides the second part of the name

The name of the ester usually ends with -anoate

Plenary

• Write three facts about carboxylic acids

• Name the ester made from these reactants

methanoic acid + ethanol

ethanoic acid + butanol

propanoic acid + methanol