Alkanes and Alkenes

Alkanes and Alkenes

1. Alkanes

   • Saturated hydrocarbons
   • Have single bonds only
     • Means they are saturated with hydrogen

2. Alkenes

   • Unsaturated hydrocarbons
   • Have at least one double bond

3. Addition reactions

   • Carbon-Carbon double bond in alkenes means another atoms can be added
     • Hydrogen and Bromine can be added in this way
   • When hydrogen is added to an alkene (hydrogenation), the corresponding alkane is formed.
   • When Bromine is added to an alkene it forms a dibromoalkane.
     • Double bond breaks and 2 bromine atoms attach
     • Its useful as it can be used to test for presence of an alkene
       • Brown/orange bromine water will react with alkenes and its colour disapears as the product formed is colourless