crude oil and fuels

• What type of resource is crude oil?

  Finite (non-renewable) resource
• How is crude oil formed?

  From remains of buried sea life
• What are the main components of crude oil?

  Mixture of hydrocarbons
• What are hydrocarbons composed of?

  Hydrogen and carbon only
• Why do modern life depend on hydrocarbons?

  They are used in fuels, solvents, and more
• What type of bonds do alkanes contain?

  Single bonds only
• What is the simplest alkane?

  Methane
• What is the displayed formula for methane?

  CH₄
• What is fractional distillation used for?

  To separate crude oil into fractions
• What are fractions in crude oil?

  Mixtures of hydrocarbons with similar chain lengths
• How is crude oil prepared for fractional distillation?

  It is vaporised before entering the column
• What happens in the fractionating column?

  Temperature decreases from bottom to top
• Where do short chain hydrocarbons condense?

  Near the top of the column
• Where do long chain hydrocarbons condense?

  Near the bottom of the column
• What are the properties of short and long chain hydrocarbons?

  • Short chains:
  • Low boiling point
  • High flammability
  • Low viscosity
  • Long chains:
  • High boiling point
  • Low flammability
  • High viscosity
• What are the names of the 4 simplest alkanes?

  Methane, ethane, propane, butane
• What occurs during complete combustion of hydrocarbons?

  Produces carbon dioxide and water
• What occurs during incomplete combustion of hydrocarbons?

  Produces water, carbon monoxide, and/or carbon
• How can you test for carbon dioxide?

  It turns lime water cloudy
• How can you test for water?

  It turns blue cobalt chloride paper pink
• How can you test for alkenes?

  They decolourise orange bromine water
• What is the purpose of cracking hydrocarbons?

  To produce shorter, more useful molecules
• What does cracking a hydrocarbon produce?

  An alkane and an alkene
• What is the general formula for an alkene?

  CₙH₂ₙ
• What are the two types of cracking?

  1. Catalytic (high temperature + catalyst)
  2. Steam cracking (very high temperature + steam)
• What distinguishes alkenes from alkanes?

  Alkenes contain a double carbon bond
• What is liquefied petroleum gas commonly known as?

  LPG
• What are the fractions obtained from crude oil in order from smallest to largest?

  • Gasoline (petrol)
  • Kerosene
  • Diesel
  • Heavy fuel oil
  • Bitumen
• What is the main use of bitumen?

  Road construction and roofing
• What is the significance of the temperature gradient in fractional distillation?

  It allows separation based on boiling points
• How does the boiling point affect the collection of fractions in fractional distillation?

  Short chains condense at lower temperatures
• What is the role of a catalyst in catalytic cracking?

  It lowers the activation energy for reactions
• Why is steam used in steam cracking?

  To provide high temperature for the reaction
• What is the main characteristic of unsaturated hydrocarbons?

  They contain double carbon bonds
• How do alkenes differ from alkanes in terms of saturation?

  Alkenes are unsaturated hydrocarbons
• How does the structure of hydrocarbons affect their properties?

  Chain length influences boiling point and viscosity
• What is the relationship between chain length and flammability in hydrocarbons?

  Short chains are more flammable than long chains
• What is the main product of complete combustion of hydrocarbons?

  Carbon dioxide and water
• What is the environmental impact of incomplete combustion?

  It produces harmful carbon monoxide
• How does the process of cracking improve the utility of hydrocarbons?

  It converts long chains into more useful shorter chains