3.1 explain the terms homologous series, hydrocarbon, saturated, unsaturated, general formula and isomerism

Homologous series
A group of compound that can all be represented by the same general formula

Hydrocarbon
Molecules made up of hydrogen and carbon atoms only

Saturated
A molecule that contains only single bonds

Unsaturated
A molecule that contains carbon-carbon double bonds (NOTE: must say carbon-carbon for the mark)

General formula
A formula that allows us to work out the number of carbon and hydrogen atoms in hydrocarbons (for example)

Isomerism
Compounds with the same molecular formula but a different display formula