Alkanes: Properties and Combustion

• Alkanes


  A homologous series of hydrocarbons that contain only carbons and hydrogen atoms with no double bonds
• Alkanes


  • As the length of the carbon chain increases:
  • Boiling point increases
  • Shorter alkanes are more volatile and evaporate more easily
  • Longer alkanes are more viscous and thick
  • Shorter alkanes are more flammable and easier to ignite or burn
• Combustion reactions


  1. Hydrocarbon reacts with oxygen to form carbon dioxide and water, releasing energy

  2. Hydrogen and carbon in the hydrocarbon are being oxidized
• Complete combustion only takes place if there is enough oxygen available
• Writing balanced equations for combustion

  1. Write unbalanced equation

  2. Balance carbon, hydrogen, oxygen atoms
• Hydrocarbons like alkanes are used as fuels because they release a lot of energy when combusted