Crude oil is a complex mixture of hydrocarbon molecules. The hydrocarbon molecules in crude oil are separated by fractional distillation. Fractional distillation is used because the different hydrocarbon molecules in crude oil have different boiling points.

1. (a)Explain why the hydrocarbon molecules in crude oil have different boiling points.[2]
2. (b)Some of the hydrocarbon molecules obtained from crude oil are processed further by cracking. Suggest why some hydrocarbon molecules are processed further by cracking.[1]
3. (c)(i)Cracking one mole of dodecane, C12H26, produces two moles of ethene and one mole of another hydrocarbon molecule. Write the equation for this cracking reaction. The ethene can be used in the production of poly(ethene).[1]
4. (c)(ii)Give the full name of the process used to produce poly(ethene) from ethene.[1]
5. (c)(iii)Give two reasons why poly(ethene) should be reused or recycled rather than just thrown away.[2]
6. (c)(iv)Part of a polymer chain, produced by the same type of process as poly(ethene), is shown. [Figure: Part of a polymer chain with repeating unit -CH2-C(COOCH3)(CH3)-] Give the displayed formula of the monomer used to produce this polymer.[2]