C7a

• What is crude oil primarily composed of?

  Hydrocarbons
• What is the purpose of fractional distillation of crude oil?

  To separate crude oil into fractions
• Which fuels can be formed from different fractions of crude oil?

  Petrol, diesel, kerosene
• What are feedstocks in the context of crude oil?

  Raw materials for making various products
• What are the steps involved in fractional distillation?

  • Heat crude oil at the bottom of the column
  • Hydrocarbons evaporate
  • Column temperature decreases from bottom to top
  • Fractions condense at different heights
  • Smaller molecules have lower boiling points
  • Larger molecules have higher boiling points
• How do the properties of larger hydrocarbons differ from smaller ones?

  Larger hydrocarbons have higher boiling points
• What does combustion of hydrocarbons produce?

  Carbon dioxide and water
• How do you balance combustion equations?

  Start with carbon, then hydrogen, then oxygen
• What is the complete combustion equation for methane?

  CH4 + 2O2 → CO2 + 2H2O
• What is the general formula for alkanes?

  CnH2n+2
• What does it mean for a hydrocarbon to be saturated?

  It contains only single bonds
• What does viscous mean?

  Thick and sticky
• What does flammable mean?

  Can burn easily
• What is cracking in the context of hydrocarbons?

  Breaking down hydrocarbons into smaller molecules
• What conditions are required for cracking?

  High temperatures and steam or a catalyst
• What are the products of cracking?

  Smaller alkanes and alkenes
• How do alkenes differ from alkanes?

  Alkenes are more reactive than alkanes
• What test can be used to identify alkenes?

  Bromine water test
• What happens to bromine water when it reacts with alkenes?

  It turns from orange to colourless
• Do alkanes react with bromine water?

  No, they do not react
• What is crude oil classified as in terms of resource availability?

  Finite resource
• How is crude oil formed?

  From ancient biomass buried in mud
• What type of hydrocarbons are alkanes?

  Saturated hydrocarbons
• What is the boiling point of a substance?

  Temperature substance changes from liquid to gas