Crude Oil

• Hydrocarbons are compunds of carbon and hydrogen atoms only.
• Carbon atoms can form four covalent bonds
• In a hydrocarbon molecule, these can be
  • carbon-carbon bonds
  • carbon hydrogen bonds
• Hydrocarbon molecules can consist of
  • chains or rings of carbon atoms

HYDROCARBONS IN CRUDE OIL

Crude oil is

• a complex mixture of hydrocarbons, with their carbon atoms in chains or rings
• an important source of useful substances 
• a finite resource

FRACTIONAL DISTILLATION

Crude oil can be separated by fractional distillation because its differerent hydrocarbons have different boiling points. During fractional distillation

• oil is heated to evaporate it
• vapours rise in the fractioning column
• the column has a temperature gradient
• each fraction condenses where it becomes cool enough, and is piped out of the column
  • The gases fraction does not condense and leaves at the top
  • The bitumen fraction does not evaporate and leaves at the bottom

Gases - domestic heating and cooking

Petrol - fuel for cars

Kersone - fuel for aircraft

Diesel Oil - fuel for some cars and trains

Fuel Oil - fuel for large ships

Bitumen - Surfacing roads

Making fractionns more useful 

• CRACKING IN THE LAB
  • the porous pot catalyst is heated strongly
  • the liquid paraffin is heated and evaporates
  • the paraffin vapour passes over the hot porous pot and the hydrocarbon molecules break down
  • one of the products is ethene which is a gas and collects in the other tube