Alcohols and carboxylic acids

Alcohols

Alcohols, also known as alkanols, have the hydroxyl functional group –OH. They are a homologous series and have the general formula {C_n}{H_{2n + 1}}OH. Their names all end in –ol.

The rules for naming an alcohol are the same as before. The hydroxyl functional group is the most important part of the molecule and the carbon chain is numbered to give it the lowest branch number.

Example

The structural formula for butan-2-ol. C atom bonded to 3 H atoms joined to C atom with 2 H atoms,  joined to another C with 1 H and hydroxyl group, joined to C with 3 H atoms.Butan-2-ol

The position of the functional group and any branches must be identified.

Methanol (CH3OH) has the structural formula of a carbon atom bonded to three hydrogen atoms and a hydroxyl group. Ethanol (C2H5OH) has the structural formula of a carbon atom bonded to three hydrogen atoms, joined to a carbon with two hydrogens and a hydroxyl group. Propan-1-ol (C3H7OH) has the structural formula of a carbon atom bonded to three hydrogen atoms, joined to a carbon with two hydrogens, which is joined to a carbon with two hydrogens and a hydroxyl group. Butan-1-ol (C4H9OH) has the structural formula of a carbon atom bonded to three hydrogen atoms is joined to a carbon with two hydrogens, which is joined to a carbon with two hydrogens, which is joined to a carbon with two hydrogens and a hydroxyl group.

Alcohols have a wide variety of uses. While ethanol is most famous for its presence in alcoholic drinks, many other alcohols exist and are commonly used as fuels and solvents. Propan-2-ol is widely used in hand gels and disinfectant wipes. Alcohols are particularly useful as fuels due to their high flammability and the fact that they burn cleanly.

The smallest alcohols, methanol, ethanol, and propanol, are miscible in water. The larger an alcohol gets, the lower the miscibility. The melting and boiling points of alcohols increase with size due to stronger intermolecular forces.

Alcohols, their general formula, functional groups and properties

Comparing the quantity of energy released by various alcohols during combustion