Addition Reactions of Alkenes

• What are alkenes classified as?

  Unsaturated hydrocarbons
• What does the term "unsaturated" mean in alkenes?

  They contain at least one carbon-carbon double bond
• What is the functional group of alkenes?

  Carbon-carbon double bond
• What elements do hydrocarbons contain?

  Only hydrogen and carbon atoms
• Why can alkenes undergo addition reactions?

  The carbon-carbon double bond can open up
• What are the three types of addition reactions for alkenes?

  1. With hydrogen
  2. With water
  3. With halogens
• What is the alkene used in the hydrogen addition reaction example?

  Propene
• What happens to the double bond in propene when hydrogen is added?

  The double bond breaks and forms propane
• What is the product formed when propene reacts with hydrogen?

  Propane
• What is the alkene used in the water addition reaction example?

  Ethene
• What conditions are required for the reaction of ethene with water?

  Catalyst and high temperatures
• What is the product formed when ethene reacts with water?

  Ethanol
• What is ethanol classified as?

  A type of alcohol
• How is ethanol separated from unreacted ethene and water?

  By cooling and fractional distillation
• Why is ethene easy to separate from the mixture?

  It has a relatively low boiling point
• What is the process used to separate ethanol from water?

  Fractional distillation
• What happens to ethanol during fractional distillation?

  It evaporates first due to lower boiling point
• What is the common halogen used in the addition reaction example?

  Bromine
• What happens when bromine is added to ethene?

  It forms dibromoethane and decolorizes
• How can alkenes be distinguished from alkanes using bromine water?

  Alkenes decolorize bromine water
• Why do alkanes not react with bromine water?

  They do not have double bonds
• What is the summary of the reactions of alkenes?

  • Alkenes are unsaturated hydrocarbons.
  • They undergo addition reactions with hydrogen, water, and halogens.
  • The double bond allows for these reactions.
  • Products include alkanes and alcohols.