Crude Oil Pt:2

• What is crude oil primarily composed of?

  A mixture of different hydrocarbons
• What process is used to separate hydrocarbons in crude oil?

  Fractional distillation
• Why are shorter hydrocarbons considered better fuels?

  They are more flammable
• What is the purpose of cracking in hydrocarbon processing?

  To break down longer hydrocarbons into shorter, more flammable ones
• What type of reaction is cracking classified as?

  A thermal decomposition reaction
• What does the term 'thermal' in thermal decomposition refer to?

  Heating
• What does 'decomposition' mean in the context of thermal decomposition?

  Breaking down molecules
• What are the two methods of cracking mentioned?

  Catalytic cracking and steam cracking
• What is the first step in both catalytic and steam cracking?

  To heat and vaporize long chain hydrocarbons
• What catalyst is used in catalytic cracking?

  Hot powdered aluminium oxide
• What happens to long hydrocarbons in catalytic cracking?

  They split apart into two smaller hydrocarbons
• In steam cracking, what is mixed with the vaporized hydrocarbons?

  Steam
• What is produced when long chain alkanes are cracked?

  A shorter alkane and an alkene
• Write the balanced equation for the cracking of decane.

  C$10$H$22$ → C$8$H$18$ + C$2$H$4$
• What is the significance of alkenes in chemical reactions?

  They can be used to produce polymers and other chemicals
• What distinguishes alkenes from alkanes?

  Alkenes have a double bond, while alkanes have only single bonds
• What happens when bromine water is added to a solution of alkenes?

  It decolorizes from orange to colorless
• Why are alkenes considered more reactive than alkanes?

  Because they have a double bond
• What are the key features of alkenes compared to alkanes?

  • Alkenes have a double bond; alkanes have single bonds.
  • Alkenes are unsaturated; alkanes are saturated.
  • Alkenes are more reactive than alkanes.
• How can alkenes form polymers?

  By breaking double bonds to form new bonds with adjacent molecules
• What is the test for alkenes?

  Adding bromine water and observing the color change
• What are the steps involved in the cracking process?

  1. Heat and vaporize long chain hydrocarbons.
  2. For catalytic cracking, pass vapor over hot powdered aluminium oxide.
  3. For steam cracking, mix vapor with steam and heat to high temperature.
  4. Split long hydrocarbons into shorter ones.
• What is the importance of balanced chemical equations in cracking reactions?

  • Ensures the conservation of mass.
  • Confirms that the number of atoms of each element is the same on both sides.
  • Helps in predicting the products of the reaction.