Cracking Crude Oil and Making Polymers

Cracking Crude Oil and Making Polymers

1. (a) Complete this sentence about crude oil.

Crude oil is mainly a mixture of compounds called ......
which contain carbon and hydrogen only.

(1)

(b) The diagram shows a laboratory experiment used to separate crude oil.

Complete each sentence by choosing the correct words from the box.

condensation distillation
evaporation melting sublimation

The main process taking place at A is ......

The main process taking place at B is ......

This method of separating crude oil is called ......

(3)

This method of separating crude oil works because the the molecules are, the their boiling point and the volatile they are.

(1)

(d) (i) The separation of crude oil produces lots of hydrocarbons with large molecules.

Choose a word from the box to complete the sentence.

condensing cracking distilling evaporating

At an oil refinery, large hydrocarbons are broken down into smaller molecules by a

process called ......

(1)

(ii) Some of the small molecules produced can be used to make polymers.

Name the polymer made from ethene.

......

(1)

(e) Crisp packets are often made from a non-biodegradable polymer. Suggest why this:

(i) is good for storing crisps

......

(2)

(ii) could be bad for the environment.

......

(1)

(Total 10 marks)

2. Tablet containers are often made from two different polymers.

(a) Ethene, C2H4, and propene, C3H6, can be made from crude oil.

(i) Complete the following sentence.

Ethene and propene are called hydrocarbons because they are made up of carbon and ...... atoms only.

(1)

(ii) Ethene molecules are used to form poly(ethene) molecules.

Complete the diagram to show the poly(ethene) molecule.

Ethene molecules Poly(ethene) molecule

(2)

(b) The tablet containers could be disposed of in a landfill site or could be recycled.

(i) Suggest two reasons why disposing of the tablet containers in a landfill site could cause problems.

1 ......

......

2 ......

......

(2)

(ii) Suggest one reason why recycling the tablet containers would be difficult.

......

(1)

(Total 6 marks)

3. The high demand for petrol (octane) can be met by breaking down longer hydrocarbons, such as decane, by a process known as cracking.

(a) Apart from heat, what is used to make the rate of this reaction faster?

......

(1)

(b) Octane is a hydrocarbon.

Give the molecular formula of octane.

......

(1)

(i) What is the name of X?

......

(1)

(ii) What is the name of the process in which X is changed into poly(ethene)?

......

(1)

(Total 4 marks)

4. The many hydrocarbons in crude oil are separated into fractions.

(a) Some of the larger hydrocarbon molecules can be broken down to produce smaller, more useful hydrocarbon molecules.

Hexane and butane are alkanes. Describe the structure of alkanes.

......

(3)

(b) Ethene is used to make poly(ethene).

This process is called polymerisation. Explain what is meant by polymerisation.

......

(2)

(Total 5 marks)

5. The diagram shows a reaction which takes place in an oil refinery.

(a) X, Y and Z are all examples of which type of compound?

......

(1)

(b) What type of chemical reaction takes place when compound X is converted into compounds Y and Z?

......

(1)

Compound Y is unsaturated. Compound Z is saturated.

(i) Suggest one use for compound Y.

......

(1)

(ii) Suggest one use for compound Z.

......

(1)

(Total 4 marks)

6. (a) Propene and propane can be produced from crude oil.

(i) A propene molecule (C3H6) can be represented by the structure shown below.

Draw a similar diagram to show the structure of a propane molecule (C3H8).

(1)

(ii) Which molecule, propene or propane, is unsaturated?

......

Give a reason for your answer

......

(1)

(b) The equation below represents the polymerisation of propene.

(i) Name the polymer produced by this reaction.

......

(1)

(ii) Explain the meaning of the term polymerisation.

......

(2)

(iii) Describe the problems caused by the everyday use of this polymer.

......

(3)

(Total 8 marks)

Wyvern Technology College 4