Crude oil, fuels and organic chemistry

• What is crude oil?

  A mixture of hydrocarbons formed over millions of years
• What does fractional distillation do?

  Separates a mixture into a number of different parts known as fractions
• What is a fraction of crude oil?

  Mixture of chemicals in the crude oil which have similar boiling points
• What is the temperature like at the bottom of the column?

  Hot
• What is the temperature like at the top of the column?

  Cool
• What happens at the top of the column?

  Substances with lower boiling points condense
• What happens at the bottom of the column?

  Substances with high boiling points condense
• What happens before crude oil enters the fractionating column?

  It is evaporated inside a furnace
• Why is crude oil evaporated in a furnace?

  So that it's vapours will condense at different temperatures when it enters the fractionating column
• What does each fraction contain?

  hydrocarbon and carbon molecules with a similar range of boiling points
• What is petroleum gases used for?

  Fuel for domestic heating and cooking
• What is petrol used for?

  Fuel for cars
• What is naptha used for?

  To make chemicals
• What is kerosene used for?

  Fuel for aircraft
• What is diesel used for?


  Fuel for some cars and trains
• What is lubricating oil used for?

  Reducing friction in machinery
• What is bitumen used for?

  Roads and roofs
• What is fuel oil used for?

  Fuel for ships and power stations
• What are features of small molecules?

  • Low boiling point
  • Very volatile
  • Flow easily
  • Ignite easily
• What are features of large molecules?

  • High boiling point
  • Not very volatile
  • Doesn't flow or ignite easily
• As you go up the fractionating column:

  • Smaller chain lengths
  • Lower boiling points
  • Higher flammability
  • Lighter colour
• What is in natural gas?

  Methane
• Where is natural gas used?

  Domestic boilers, Bunsen burners and some power stations
• How has coal formed?

  From the remains of ancient forests
• What is in coal?

  Carbon and sulfur
• What is produced when coal is burnt?

  Sulfur dioxide
• What does sulfur dioxide cause?

  Acid rain
• What does burning fossil fuels lead to?

  Climate change
• Why is crude oil so important to the economy?

  The majority of society depends on it
• How is the price of crude oil determined?

  By oil companies
• What does crude oil provide countries (who produce it) with?

  Great political power. They can turn off the supply of crude oil to other countries
• How would war affect the production of crude oil?

  Can restrict access to supplies, causing huge disruption in the oil industry
• How does oil spillages affect the environment?

  Pollutes wildlife and their surroundings, therefore killing them off
• What issues do oil powered stations cause in terms of their plot?

  Take up a lot of land and destroy animal habitats
• Why are large hydrocarbon molecules not efficient?

  They don't flow as easily and are difficult to ignite
• What does cracking do?

  Allows for large hydrocarbon molecules to be broken down into smaller, more useful hydrocarbons
• How are large hydrocarbon molecules cracked?

  Heated to 600-700 degrees and passed over a catalyst of either silica or alumina
• What happens in cracking?

  Covalent bonds are broken in the molecules which causes thermal decomposition
• What does cracking produce?

  Smaller alkanes and alkenes
• There is a greater demand for smaller hydrocarbon molecules than larger ones