Properties of Hydrocarbons

• How do Hydrocarbons differ from each other

  • Size of molecules
  • Length of molecules
• Shorter molecules = less viscous ( runny )

  
  

  Longer molecules = more viscous
• Shorter molecules = lower melting point

  
  

  Longer molecules = higher melting point
• Shorter molecules = more flammable, easier to ignite

  
  

  Longer molecules = less flammable, harder to ignite
• The intermolecular forces of attraction break a lot more easily in small molecules than they do in bigger molecules
• Shorter hydrocarbons

  • Easy to ignite
  • Low melting points
  • Usually a gas at room temperature
• Longer hydrocarbons

  • Harder to ignite
  • High melting points
  • Usually liquid at room temperature
• The stronger the force between hydrocarbon molecules the harder it is for the liquid to flow