Edexcel IAL Chemistry Topic 5 Checklist
(2025–2026 Exams)
Topic 5: Alkenes
Know the general formula of alkenes
and understand that alkenes and cycloalkenes are hydrocarbons
which are unsaturated
(have a carbon-carbon double bond which consists of a σ bond
and a π bond
)
Be able to explain geometric isomerism
in terms of restricted rotation around a C=C double bond and the nature of the substituents on the carbon atoms
Understand the E–Z naming system
for geometric isomers and why it is necessary to use this when the cis- and trans- naming system breaks down
Be able to describe the reactions of alkenes, limited to:
– The addition of hydrogen, using a nickel catalyst, to form an alkane
– The addition of halogens to produce a di-substituted halogenoalkane
– The addition of hydrogen halides to produce mono-substituted halogenoalkanes
– The addition of steam, in the presence of an acid catalyst, to produce alcohols
– Oxidation of the double bond by acidified potassium manganate(VII) to produce a diol
– The addition of hydrogen, using a nickel catalyst, to form an alkane
– The addition of halogens to produce a di-substituted halogenoalkane
– The addition of hydrogen halides to produce mono-substituted halogenoalkanes
– The addition of steam, in the presence of an acid catalyst, to produce alcohols
– Oxidation of the double bond by acidified potassium manganate(VII) to produce a diol
Know the qualitative test for a C=C double bond
using bromine or bromine water
Be able to describe the mechanism (including diagrams), giving evidence where possible, of:
– The electrophilic addition of bromine and hydrogen bromide to ethene
– The electrophilic addition of hydrogen bromide to propene
(Use of the curly arrow notation is expected – the curly arrows should start from either a bond or from a lone pair of electrons. Knowledge of the relative stability of primary, secondary and tertiary carbocation intermediates is expected.)
– The electrophilic addition of bromine and hydrogen bromide to ethene
– The electrophilic addition of hydrogen bromide to propene
(Use of the curly arrow notation is expected – the curly arrows should start from either a bond or from a lone pair of electrons. Knowledge of the relative stability of primary, secondary and tertiary carbocation intermediates is expected.)
Be able to describe the addition polymerisation
of alkenes and draw the repeat unit given the monomer, and vice versa
Understand how chemists limit the problems caused by polymer disposal by:
– Developing biodegradable polymers
– Removing toxic waste gases produced by the incineration of polymers
– Developing biodegradable polymers
– Removing toxic waste gases produced by the incineration of polymers
Further suggested practicals:
– Investigating the difference in reactivity of alkanes and alkenes, including combustion, reaction with bromine water, reaction with acidified potassium manganate(VII)
– Preparation of cyclohexene from cyclohexanol
– Preparation of limonene from orange peel by steam distillation
– Preparation of Perspex® from methyl 2-methylpropenoate
– Investigating the difference in reactivity of alkanes and alkenes, including combustion, reaction with bromine water, reaction with acidified potassium manganate(VII)
– Preparation of cyclohexene from cyclohexanol
– Preparation of limonene from orange peel by steam distillation
– Preparation of Perspex® from methyl 2-methylpropenoate
