Hydrocarbons

• What is organic chemistry primarily concerned with?

  Compounds that contain carbon
• What are hydrocarbons?

  The simplest organic compounds containing carbon
• What elements do hydrocarbons contain?

  Hydrogen and carbon atoms only
• Is CH.4 a hydrocarbon? Why or why not?

  Yes, it contains only carbon and hydrogen
• What type of bonds do alkanes have?

  All C—C single bonds
• What is the general formula for alkanes?

  CH.2n+2
• What is a homologous series?

  A group of compounds that react similarly
• What does it mean for alkanes to be saturated hydrocarbons?

  Each carbon forms four single covalent bonds
• What are the first four alkanes?

  • Methane (CH.4)
  • Ethane (C.2H.6)
  • Propane (C.3H.8)
  • Butane (C.4.H.10)
• What is a displayed formula?

  A drawing showing all atoms and bonds
• How do hydrocarbon properties change with chain length?

  Properties change as the carbon chain lengthens
• What happens to the viscosity of hydrocarbons as the carbon chain shortens?

  They become less viscous and more runny
• How does volatility change with carbon chain length?

  Shorter chains are more volatile
• What does "more volatile" mean for hydrocarbons?

  Turns into gas at lower temperatures
• How does flammability change with carbon chain length?

  Shorter chains are more flammable
• Why are short-chain hydrocarbons used as bottled gases?


  They have lower boiling points and are stored as liquids
• What occurs during complete combustion of hydrocarbons?

  Releases energy, producing CO₂ and water
• What is oxidation in the context of combustion?

  Gain of oxygen during combustion
• Why are hydrocarbons used as fuels?

  They release a lot of energy when combusted
• How do you write a balanced equation for methane combustion?

  CH.4 + 2O.2 → CO.2 + 2H.2O
• How do you balance the carbon and hydrogen in the combustion of methane?

  One CO.2 and two H.2O are needed
• How do you balance the oxygen in the combustion of methane?

  Two O.2 are needed for balance
• Why are alkanes considered useful fuels?

  They release energy when burnt efficiently