The alkanes are a homologous series of organic molecules. Alkanes are generally unreactive and are commonly used as fuels.

1. (a)Define homologous series.[2]
2. (b)Give two reasons to explain the general unreactivity of alkanes. 1 2[2]
3. (c)Alkanes with low relative molecular mass, Mᵣ, are more useful than those found in heavier crude oil fractions. Name the process that is used to obtain alkanes with low Mᵣ from heavier crude oil fractions.[1]
4. (d)(i)Hexane, C₆H₁₄, has four structural isomers. Fig. 3.1 shows hexane and two of its structural isomers. [Figure 3.1] Complete Fig. 3.1 by drawing structures for C and D, the other two structural isomers of hexane.[2]
5. (d)(ii)A, B and hexane have different boiling points. Arrange A, B and hexane in order of increasing boiling point. Explain your answer. lowest ............................ < ............................ < ............................ highest[3]
6. (e)(i)Hexane can be converted into compounds E and F at high temperature and pressure. Fig. 3.2 shows the reaction scheme involving hexane, E and F. [Figure 3.2] Identify a suitable reagent for reaction 3.[1]
7. (e)(ii)Use the data in Fig. 3.2 and in Table 3.1 to calculate the enthalpy change of reaction 2, ΔH₂. [Table 3.1] ΔH₂ =[2]
8. (e)(iii)Write an equation for the complete combustion of hexane.[1]

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