Petroleum is a complex mixture of naturally occurring hydrocarbon compounds found in rock which has been formed over thousands of years by heat and pressure turning organic matter to oil and gas. Impurities such as sulphur, oxygen and nitrogen are common in petroleum.
Petroleum is a complex mixture of naturally occurring hydrocarbon compounds found in rock which has been formed over thousands of years by heat and pressure turning organic matter to oil and gas. Impurities such as sulphur, oxygen and nitrogen are common in petroleum.