4.1 Three reactions of organic compounds from the same homologous series are shown below.

4.1.1 Define a homologous series. (2)
4.1.2 Name the type of reaction represented by I. (1)
4.1.3 Write down the formula of the inorganic compound P. (1)
4.1.4 Give the structural formula of a POSITIONAL isomer of
2-bromobutane. (2)
4.1.5 Using molecular formulae, write down the balanced equation for
reaction II. (3)
Reaction III is an example of a cracking reaction.
4.1.6 Define a cracking reaction. (2)
4.1.7 Give the structural formula of organic compound Q. (2)
4.2 Study the flow diagram below.

4.2.1 Write down the IUPAC name of compound R. (2)
4.2.2 Compound R reacts in the presence of concentrated phosphoric
acid to form an alkene.
Write down the structural formula of the MAJOR PRODUCT in this reaction. (2)
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