Crude oil and hydrocarbons

Hydrocarbons are compounds that contain hydrogen and carbon atoms only.

Crude oil

Crude oil is a complex mixture of hydrocarbons. Carbon atoms can form four covalent bonds, and join together to form chains and rings in hydrocarbon molecules.

In the ball and stick models below, carbon atoms are black and hydrogen atoms are white.

Two examples of hydrocarbon molecule chains.Some examples of hydrocarbon molecules

Crude oil is a finite resource because it is made extremely slowly over millions of years, or is no longer being made. However, crude oil is an important source of:

A feedstock is a raw material used to provide reactants for an industrial reaction. A petrochemical is a substance made from crude oil using chemical reactions. For example, ethene is produced from crude oil. It is used as feedstock to make poly(ethene), a polymer.