6.1.3 Carboxylic Acids and Esters: Module 6: Organic Chemistry & Analysis Chemistry OCR A A Level

What is the functional group of a carboxylic acid?

-COOH (C=O and C-OH)

How do you name carboxylic acids?

-oic acid

Are carboxylic acids soluble in water? Why? What influences their solubility.

Yes. Acid group can form hydrogen bonds with water molecules.

What are the intermolecular forces in carboxylic acids?

Hydrogen bonds in solid state - very strong.

What are esters (what are they formed from)? Functional group, general formula?

Formed from carboxylic acids and alcohols.

RCOOR’ (C=O, C-O-C)

How do you name esters?

Start with the alcohol group that has replaced the hydrogen, then acid part e.g. propyl (from alcohol) ethanoate (from carboxylic acid).

What characteristic physical properties do esters have?

Volatile, pleasant fruity smells e.g. apple, pear drops.

What are some uses of esters?

Flavourings, perfumes (both for longer chains), solvents (short chains), plasticisers.

How could you distinguish carboxylic acids from other -OH containing compounds?

Add NaHCO3 , acids will produce sodium salt, water and carbon dioxide.

Write an equation for the reaction of ethanoic acid with NaOH.

CH3COOH + NaOH → H2O + CH3COO- Na+

Write an equation for the reaction of ethanoic acid with calcium oxide

2CH3COOH + CaO → (CH3COO)2 Ca + H2O

What catalyst is needed for the formation of esters from alcohols and carboxylic acids?

Concentrated strong acid. e.g. H2SO4

What catalyst is needed for the hydrolysis of esters?

Dilute strong acid. e.g. H2SO4

What is an alternative method of hydrolysis?

Base hydrolysis

What are the advantages of base hydrolysis?

Reaction goes to completion due to neutralisation by base - more product in the mixture than acid catalysed hydrolysis.