Alkenes

• What is the family of hydrocarbons that includes alkenes?

  Alkenes
• What type of bond do all alkenes contain?

  A carbon-carbon double bond
• How can alkenes be produced from alkanes?

  By cracking
• Why are alkenes more reactive than alkanes?

  Because they contain a carbon-carbon double bond
• What is the functional group of alkenes?

  • The functional group is >C=C<
• What is the general formula for alkenes?

  C_nH_2n
• Why are alkenes classified as unsaturated hydrocarbons?

  Because they contain one or more double bonds
• What reaction occurs when alkenes react with bromine?

  They produce dibromoalkanes
• How can bromine water be used to distinguish between an alkane and an alkene?

  Alkenes decolorize bromine water, while alkanes do not
• How do you draw the structural and displayed formulae for alkenes with up to four carbon atoms?

  • Use the C=C bond to connect carbon atoms
  • Ensure correct hydrogen counts for each carbon
  • Follow the rules for structural and displayed formulae
• What is the minimum number of carbon atoms required to form an alkene?

  Two carbon atoms
• What are the first three alkenes and their molecular formulas?

  1. Ethene - C₂H₄
  2. Propene - C₃H₆
  3. But-1-ene - C₄H₈
• What are the structural and displayed formulae for the first three alkenes?

  1. Ethene:

  • Structural: CH₂=CH₂
  • Displayed: CH₂=CH₂

  1. Propene:

  • Structural: CH₂=CH-CH₃
  • Displayed: CH₂=CH-CH₃

  1. But-1-ene:

  • Structural: CH₂=CH-CH₂-CH₃
  • Displayed: CH₂=CH-CH₂-CH₃