cracking

• What is meant by cracking in chemistry?

  Breaking down long chain hydrocarbons
• What are the conditions for catalytic cracking?

  High temperature and a catalyst
• What is the general formula for alkanes?

  $C_nH_{2n+2}$
• Why are long chain hydrocarbons not good fuels?

  They are not very flammable
• What is produced when cracking a long chain alkane?

  Shorter chain hydrocarbons and alkenes
• What is an alkene?

  A hydrocarbon with a double bond
• How do alkenes differ from alkanes in terms of reactivity?

  Alkenes are more reactive than alkanes
• What test is used to identify alkenes?

  Using bromine water
• What happens to bromine water when it reacts with an alkene?

  It turns colorless
• How do you balance a chemical equation for cracking?

  Ensure carbon and hydrogen atoms are equal
• In a cracking equation, if the left side has 25 carbon and 52 hydrogen atoms, what must the right side total?

  Must also total 25 carbon and 52 hydrogen
• If a cracking reaction has 40 carbon and 82 hydrogen atoms on the left, how many are in the first product?

  33 carbon and 68 hydrogen atoms
• What are the two types of cracking methods?

  • Catalytic cracking
  • Uses high temperature and a catalyst
  • Steam cracking
  • Uses high temperature and steam
• What are the uses of alkenes?

  • Used to make polymers
  • Starting material for other chemicals
• What is the significance of the double bond in alkenes?

  • Makes alkenes more reactive than alkanes
  • Allows for addition reactions