Crude oil

How crude oil was formed Microscopic plants and animals die and fall to the sea bed Layers of sand and mud form on top Pressure and high temperature cause oil to form Oil obtained by drilling

What is crude oil? Pentane

Where does crude oil come from?

The Fractional Distillation of Crude Oil Average number of C atoms in chain Fraction Boiling pt. 3 Liquid petroleum gas < 25oC 40oC Petrol (gasoline) 25 – 60oC 8 Naphtha 60 – 180oC 10 Paraffin 180 – 220oC 12 Diesel 20 220 – 250oC Fuel oil 40 250 – 300oC Lubricating oil 80 300 – 350oC Bitumen 120 > 350oC 350oC Heated Crude Oil

How do we separate the chemicals in crude oil?

Properties of the fractions

The compounds produced by the distillation of crude oil are all hydrocarbons. Hydrocarbons are compounds which contain the elements hydrogen and carbon.

Naming hydrocarbons Alkanes Methane Ethane Propane CH4 C2H6 C3H8 These hydrocarbons are said to be saturated. (They have single bonds between carbon atoms).

Fuels Most alkanes are used as fuels to produce useful forms of energy. When completely burned alkanes form carbon dioxide and water.

Equations for combustion CH4 methane + O2 oxygen 2 CO2 carbon dioxide + H2O water 2 C3H8 + O2 CO2 + H2O 5 3 4 C2H4 + O2 CO2 + H2O 3 2 2

Combustion of hydrocarbons When burned with sufficient oxygen, hydrocarbons form carbon dioxide and water

Alkenes Test for an unsaturated hydrocarbon (an alkene) Ethene C2H4 Alkenes are said to be unsaturated Test for an unsaturated hydrocarbon (an alkene) Add unsaturated compound Shake