Naphtha is a mixture which contains only hydrocarbon molecules.

1. (a)(i)What is meant by the term hydrocarbon?[1]
2. (a)(ii)Name the raw material that is used to produce a sample of naphtha.[1]
3. (b)(i)Compound V is found in naphtha. It has a molecular formula C₁₀H₂₂. When V is heated at high pressure in the absence of air, an equal number of moles of ethene, propene and W are made. W is a compound made of straight chain, saturated molecules. Name the process that describes this reaction.[1]
4. (b)(ii)Deduce the structure of W. Draw its structure below.[1]
5. (c)(i)Propene is separated from the mixture and heated in air in the presence of a catalyst. Propene is oxidised to X, which contains two functional groups. Effervescence is seen when Na₂CO₃(aq) is added to X. Identify the functional group present in X which is responsible for this observation.[1]
6. (c)(ii)Identify a reagent which could be used to show that X contains a C=C. Include relevant observations.[2]
7. (d)X reacts with another reagent to form Y. Molecules of Y react together to form addition polymer Z. The diagram shows the repeat unit of polymer Z. [Figure X.X] Draw the structural formula of monomer Y.[1]
8. (e)(i)Polymer Z is useful because it absorbs large amounts of water. However, there are problems associated with the disposal of products containing polymer Z. Combustion is not an appropriate method to dispose of pure Z because the process releases harmful gases. Some of these gases contribute to the enhanced greenhouse effect. Identify a gas released during the combustion of Z which contributes to the enhanced greenhouse effect.[1]
9. (e)(ii)Identify another gas which could be produced during the combustion of pure Z. Describe a consequence, other than the enhanced greenhouse effect, of its release into the atmosphere. gas consequence[1]

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