Crude Oil - Substances from Crude Oil

Crude oil provides us with many useful substances, some of them quite obvious like plastics, or the fuels petrol and diesel. There are some, however, that are a little less obvious including bubble gum and lipstick. You need to know about a number of these substances for GCSE Chemistry, and also some of the main processes that they must go through to make them useful.

Crude oil is an important source of the chemicals that are needed to manufacture plastics. It was formed by the anaerobic decay of dead marine plants and animals as the mud on the bottom of the sea gradually turned into rock over a time period of millions of years. Oil is a liquid and can therefore flow through pores and cracks in rock. It is less dense than the surrounding rock and it is under pressure because of the weight of the rocks above so it will rise upwards. If it reaches an impermeable rock layer, it becomes trapped - otherwise it just seeps out at the surface of the Earth. Drilling a hole through the impermeable rock allows us to release the oil trapped underground.