Functional group chemistry

Functional group chemistry examines the behaviour and reactions of functional groups in organic compounds.
A functional group is a group of atoms that largely determines the chemical properties of the compound.
Functional groups often involve atoms of elements such as oxygen, nitrogen, sulphur, or the halogens, in addition to carbon and hydrogen.
Various types of functional groups include: alcohols (OH), amines (NH2), aldehydes (CHO), ketones (C=O), carboxylic acids (COOH), and esters (COO).

Alcohols contain one or more hydroxyl groups (OH) attached to a carbon atom.
Alcohols can be primary, secondary, or tertiary, depending on whether the carbon bonded to the OH group is attached to one, two, or three other carbon atoms.
Reactions involving alcohols commonly include oxidation (by acidified potassium dichromate) and esterification (reaction with carboxylic acids).

Amines possess an amine group (NH2), a nitrogen atom bonded to one or more hydrogens or carbon compounds.
Amines can be categorized as primary, secondary, or tertiary, akin to alcohols.
Amines play a vital role in forming amides via condensation reactions with carboxylic acids, and in base reactions caused by the lone pair of electrons on the nitrogen.

Both Aldehydes and Ketones have a carbonyl group (C=O) as their functional group.
In aldehydes, the carbonyl group is at the end of a carbon chain while in ketones it’s within the chain.
Major reactions for these groups are oxidation (aldehydes can be oxidised into carboxylic acids) and nucleophilic addition.

Carboxylic acids contain a carboxyl group (COOH), making them weak acids.
Esters contain a ester group (COO) that is derived from a carboxylic acid and an alcohol.
Carboxylic acids can undergo neutralisation (forming salts), and condensation (forming esters).
Esters undergo hydrolysis (forming carboxylic acids and alcohols).