Aliphatic hydrocarbon - hydrocarbons that do not contain a benzene ring

Aromatic hydrocarbon - hydrocarbons that contain a benzene ring

Benzene - a hydrocarbon that contains a ring of six carbon atoms with alternating double and single bonds and six attached hydrogen atoms

Coal - a kind of combustible black / dark brown solid

Endothermic reaction - a reaction in which heat is taken in

Exothermic reaction - a reaction in which heat is released

Fossil fuel - formed from the remains of plants and animals that lived millions of years ago

Fraction - mixtures of hydrocarbons with boiling points within certain ranges obtained from fractional distillation

Fractional distillation - a process that separates mixture of hydrocarbons with different boiling points into groups 

Greenhouse effect - the phenomenon that some of the infrared energy (heat) being trapped by greenhouse gases which act like the glass of a greenhouse, causing the Earth to become warmer

Greenhouse gas - gases that can trap infrared energy coming from the sun, such as carbon dioxide and water vapour

Hydrocarbon - compounds that contain only atoms of carbon and hydrogen

Natural gas - a mixture of combustible gases

Petroleum - a mixture of hydrocarbons which is a dark, sticky liquid and is difficult to burn

Volatile organic compound - unburnt hydrocarbons that are easily evaporated