Some reactions are shown, based on methylpropan-2-ol, (CH3)3COH. [Figure showing reaction scheme: (CH3)3CBr (reaction 1) → (CH3)3COH (reaction 2) → (CH3)2C=CH2 (reaction 3) → (CH3)3CBr and (CH3)2CHCH2Br (reaction 4)] 1-bromobutane is a structural isomer of the product of reaction 1. The product of reaction 3, methylpropene, does not show stereoisomerism.

1. (a)For each of the reactions state the reagent(s), the particular conditions required, if any, and the type of reaction. For the type of reaction choose from the list. Each type may be used once, more than once or not at all. Each reaction may be described by one or more than one type. hydrolysis dehydration substitution oxidation addition condensation reaction | reagent(s) and conditions | type(s) of reaction 1 | | 2 | | 3 | | 4 | | [5]
2. (b)Draw a diagram to show the SN1 mechanism of reaction 2. Include all necessary charges, dipoles, lone pairs and curly arrows.[3]
3. (c)(i)Define the term structural isomer and name the three different types of structural isomerism. definition types of structural isomerism 1 2 3[4]
4. (c)(ii)1-bromobutane is treated with the same reagents as in reaction 2. Butan-1-ol is formed. Identify the mechanism of this reaction. Explain why this reaction proceeds via a different mechanism from that of reaction 2. mechanism explanation[3]
5. (d)(i)Give two reasons why methylpropene does not show stereoisomerism.[2]
6. (d)(ii)Methylpropene can be polymerised to form a poly(alkene). State the type of polymerisation and draw the repeat unit of the polymer formed from methylpropene. type of polymerisation repeat unit[3]
7. (d)(iii)State the difficulty associated with the disposal of poly(alkenes).[1]
8. (e)Name the two products of reaction 4. name of (CH3)3CBr name of (CH3)2CHCH2Br[2]

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