Organic chemistry written questions
Practise G3 Science organic structures, reactions and fuel applications in written questions, with marking guidance after submission.
Learning goals
- Name natural gas, mainly methane, and crude oil as non-renewable energy sources
- Describe crude oil as a mixture of hydrocarbons separated by fractional distillation into fractions used as fuels and as a source of chemicals
- Describe biofuels, such as bioethanol from sugarcane, as a renewable alternative to natural gas and crude oil
- Describe how biofuels are more sustainable than fossil fuels because plants take in carbon dioxide as they grow, offsetting what burning releases
- Describe a homologous series as compounds with a general formula, similar chemical properties and physical properties that change gradually as the molecules get bigger
- Describe the alkanes as a homologous series of saturated hydrocarbons with general formula CₙH₂ₙ₊₂
- Draw and name the unbranched alkanes methane to propane
- Describe alkanes, such as methane, as generally unreactive apart from combustion and substitution by chlorine
- Describe the alkenes as a homologous series of unsaturated hydrocarbons with general formula CₙH₂ₙ
- Draw and name the unbranched alkenes ethene and propene
- Describe how cracking makes alkenes and hydrogen, and why cracking is needed to meet demand for fractions of smaller molecules
- Distinguish saturated from unsaturated hydrocarbons by their structures and with aqueous bromine
- Describe the combustion, polymerisation and addition reactions with bromine and hydrogen of alkenes such as ethene
- State what polyunsaturated means on food products
- Describe how margarine is made by adding hydrogen to unsaturated vegetable oils to form a solid
- Describe alcohols as a homologous series with the –OH functional group
- Draw and name the unbranched alcohols methanol to propanol
- Describe the combustion of alcohols and their oxidation to carboxylic acids
- Describe how ethanol is made by fermenting glucose
- Describe the carboxylic acids as a homologous series containing the –CO₂H group
- Describe how ethanol is oxidised to ethanoic acid by oxygen in air or acidified potassium manganate(VII)
- Describe polymers as large molecules built from small monomer units, with different polymers having different units
- Describe how ethene monomers form poly(ethene) by addition polymerisation
- State uses of poly(ethene) as a typical plastic, such as plastic bags and cling film
- Deduce an addition polymer's structure from its monomer, and the reverse
- Describe the pollution caused by disposing of non-biodegradable plastics
- Describe physical recycling of plastics, such as melting poly(ethene) waste into pellets
- Describe chemical recycling of plastics, such as cracking plastic waste into fuel
- Discuss the social, economic and environmental issues of recycling plastics
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Paper instructions
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