alkenes

• the general formula of alkene is C $_n$ H $_{2n}$
• alkenes have one double covalent bond between two carbon atoms
• alkenes are used to make polymers and other useful chemicals
• the functional group of alkenes is the carbon to carbon double bond
• alkenes all react in a similiar way because they all have the same functional group
• the functional group is a part of a molecules that determines how it reacts
• combustion of alkenes

  • produces carbondioxide and water
  • it also produces unburnt carbon because its an incomplete combustion
  • alkenes burn in the air with a smokey flame
• hydrogenation of alkenes

  • the temperature should be 150 degrees
  • nickel catalyst
  • double bonds turn to a single bond and it produces an alkane
• hydration

  • reaction of alkenes with steam
  • to produce and alcohol
  • the temperature must be at 300 degrees
  • the pressure must be at 70 atm
  • use phosphoric acid as a catalyst
  • the reaction is reversible
  • to get a high yeild pass the ethene and steam back through the catalyst
• halogens and alkenes

  • it is a very rapid reaction
  • produces a dihaloalkane