Fractional Distillation

• What is crude oil primarily used for?

  To make fuels and other useful products
• Why can't crude oil be used directly in cars?

  It needs to be separated into hydrocarbons
• What is crude oil classified as?

  A fossil fuel
• How is crude oil formed?

  From remains of plants and animals over millions of years
• What are fossil fuels like coal, oil, and gas classified as?

  Non-renewable fuels
• Why are fossil fuels considered finite resources?

  They are used faster than they are renewed
• What is the main component of crude oil?

  Liquid hydrocarbons
• What process is used to separate the compounds in crude oil?

  Fractional distillation
• What are the approximate numbers of carbons in hydrocarbon fractions?

  • LPG: 3 (propane, butane)
  • Petrol: 5-12
  • Kerosene: 12-15
  • Diesel Oil: 15-20
  • Heavy fuel oil: 20-40
• What are hydrocarbons made up of?

  Hydrogen and carbon atoms
• What happens to crude oil during fractional distillation?

  It is heated until most turns into gas
• What is the temperature gradient in the fractional column?

  Hot at the bottom, cooler at the top
• Why do longer hydrocarbons condense earlier in the column?

  They have higher boiling points
• What is the result of fractional distillation of crude oil?

  Separation into different hydrocarbon fractions
• What do the fractions from fractional distillation have in common?

  Similar number of carbon atoms
• What are the steps involved in fractional distillation?

  1. Heat crude oil until it vaporizes
  2. Gases enter a fractional column
  3. Temperature gradient allows separation
  4. Longer hydrocarbons condense early
  5. Shorter hydrocarbons condense later
  6. Collect different fractions