Topic 2 Alkanes

• What is general formula for alkanes? [1]

  CnH2n+2
• Alkanes are saturated
• You separate crude oil by fractional distillation because the long hydrocarbons aren’t that useful
• Describe the process of fractional distilation [4]

  Crude oil is vaporised at 350 degrees

  The vaporised oil goes into a fraction in column and rises up the trays. The larger hydrocarbons have high by and don’t vaporise.

  Each hydrocarbon condenses at different temperatures

  Shortesr hydrocarbons are released as gases
• Conditions for thermal cracking [3]

  High temperature and high pressure

  Produces a lot of alkanes

  these alkanes are used to make valuable products
• Conditions needed for catalytic cracking [3]

  Uses a zeolite catalyst, at a slight pressure and high temperature

  It produces aromatic hydrocarbons and motor fuels

  Using a catalyst cuts cost
• Carbon monoxide is removed using a catalystic converter
• What is a free radical ?[1]

  A particle with an unpaired electron
• How does a free radical form? [2]

  Forms when a covalent bond splits equally, giving one electron to each atom
• What is the equation for the depletion of the ozone layer? [1]

  o2 -> o. + o.
• Look at notes for initiation propagation and termination