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L02. Making Crude Oil More Useful. Connector: (Grade D) How is oil obtained? List some of the environmental problems involved. Write down a question based on these photos Then share this with a small group. Does cleaning a bird’s feathers help?.
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L02. Making Crude Oil More Useful • Connector: (Grade D) • How is oil obtained? • List some of the environmental problems involved.
Write down a question based on these photos • Then share this with a small group.
Does cleaning a bird’s feathers help? What happens when water is dripped onto a bird’s feather? What substance is used to remove the crude oil from a bird’s feathers? What effect does this have on the bird’s feathers? http://www.youtube.com/watch?v=KddYr4l6bqQ
Homework • Homework task: Supply and Demand Task Sheet • Due date: • Criteria for Grade C: • Criteria for Grade B: • Criteria for Grade A/A*:
BIG picture • What skills will you be developing this lesson? • ICT • Numeracy • Literacy • Team work • Self management • Creative thinking • Independent enquiry • Participation • Reflection • How is this lesson relevant to every day life? (WRL/CIT)
Task 1 (Grade C) • Keywords for Task 1: • cracking • catalyst • Task 1: Describe how large hydrocarbon molecules may be converted into smaller ones • Task 1: Extension
Distillation tower pressure Catalytic cracker Heat to vaporise Catalytic Cracking • Large hydrocarbons are broken into smaller molecules using pressure, heat and a catalyst. • This process is known as catalytic cracking. • The small molecules produced are then separated by fractional distillation. Fractional distillation tower Smaller molecules Big Molecules Molecules break up
Cracking a hydrocarbon in the laboratory WARNING – to prevent suck back of water remove the water trough as soon as you stop heating the boiling tube. • Collect two test tubes of gas: • Carefully ignite the gas in one of the tubes. • Carefully add bromine water to the other tube, replace the stopper and gently shake.
Task 1: Summary – Copy and complete Catalytic Cracking • Large hydrocarbons are broken into smaller molecules using pressure, heat and a catalyst. • This process needs a lot of energy because strong chemical bonds are being broken. • The small molecules produced are then separated by fractional distillation. • When carried out in the laboratory broken pottery is used as the catalyst. catalyststrong smaller pressure energy fractional distillation broken pottery heat
Task 1: Review Go back to your lesson outcome grid and fill out the ‘How I did’ and the ‘Targets’ column.
Task 2 (Grade B) • Keywords for Task 2: • alkane • alkene • saturated • unsaturated • Task 2: Explain why cracking is carried out. • Task 2: Extension
Making better use of Crude Oil • Small hydrocarbons are much more useful than those with long chains. • Crude oil contains lots of large molecules. • These long chain hydrocarbons are broken down, by cracking, into the more useful shorter chain molecules. Small molecules Big molecules Medium molecules
Octane Heat pressure catalyst hexane ethene + Catalytic Cracking • In the catalytic cracker long chain molecules are split apart or ‘cracked’. An example of such a reaction is: C=C Used to make plastics Used as a fuel C8H18 C6H14 + C2H4
Activity decane H H H H H H H H H H H H H C C C C C C C H H C C C C C Heat pressure H H catalyst H H H H H H H H H H H H H H H H + H C C C C C C H H H H H H ethene octane • Draw out displayed formulae of a pair of products formed by cracking decane
Saturated or Unsaturated? • Alkanes are saturated. • Saturated means “full up”. • Every carbon atom has already used all four of it’s bonds to join to four other atoms. No other atoms can be added. • Alkanes have C-C single bonds. • Alkenes are unsaturated. • Alkenes have a C=C double bond that could instead become two single bonds. This means that other atoms can be added. It is not “full up”. • Alkenes are reactive compounds, and are often used to make polymers.
Task 1: Summary • Write a sentence to explain: • Why cracking is carried out. • What the products of cracking are used for. • The difference between an alkane and an alkene. • Compare your answers with your neighbour.
Task 2: Review Go back to your lesson outcome grid and fill out the ‘How I did’ and the ‘Targets’ column.
Task 3: (Grade A/A*) • Task 3: Discuss in simple terms the political problems associated with the exploitation of crude oil. See page 7 in your text books, read through the appropriate section, and then write your own summary. • Task 3: Extension • Keywords for Task 3: • supply and demand • oil refinery • cracking
Task 3: Review Go back to your lesson outcome grid and fill out the ‘How I did’ and the ‘Targets’ column.
Review of lesson Can you explain these key words? • Catalyst, • Cracking, • Oil refinery • Petrochemical • Over-supply • Alkane • Alkene
Technician’s list Demo – water & oil on a feather Large feather Vegetable oil Washing up liquid Washing up bowl Cracking experiment Per group Boiling tube with mineral wool soaked in paraffin oil and broken pottery catalyst Delivery tube & bung Water trough 2x test tubes & stoppers Bromine water Splints Clamp stands bunsens