11.1 Fuels and crude oil

(a) name natural gas, mainly methane, and petroleum as sources of energy

(b) describe petroleum as a mixture of hydrocarbons and its separation into useful fractions by fractional distillation (see also 1.2(a))

(c) name the following fractions and state their uses

(i) petrol (gasoline) as a fuel in cars

(ii) naphtha as the feedstock and main source of hydrocarbons used for the production of a wide range of organic compounds in the petrochemical industry (see also 11.1(d))

(iii) paraffin (kerosene) as a fuel for heating and cooking and for aircraft engines

(iv) diesel as a fuel for diesel engines

(v) lubricating oils as lubricants and as a source of polishes and waxes

(vi) bitumen for making road surfaces

(d) describe the issues relating to the competing uses of oil as an energy source and as a chemical feedstock (see also 11.1(c)(ii)).

11.2 Alkanes

(a) describe a homologous series as a group of compounds with a general formula, similar chemical properties and showing a gradation in physical properties as a result of increase in the size and mass of the molecules, e.g. melting and boiling points; viscosity; flammability

(b) describe the alkanes as a homologous series of saturated hydrocarbons with the general formula CnH2n+2

(c) draw the structures of branched and unbranched alkanes, C1 to C4, and name the unbranched alkanes methane to butane

(d) define isomerism and identify isomers

(e) describe the properties of alkanes (exemplified by methane) as being generally unreactive except in terms of combustion and substitution by chlorine.

11.3 Alkenes

(a) describe the alkenes as a homologous series of unsaturated hydrocarbons with the general formula CnH2n

(b) draw the structures of branched and unbranched alkenes, C2 to C4, and name the unbranched alkenes ethene to butene

(c) describe the manufacture of alkenes and hydrogen by cracking hydrocarbons and recognise that cracking is essential to match the demand for fractions containing smaller molecules from the refinery process

(d) describe the difference between saturated and unsaturated hydrocarbons from their molecular structures and by using aqueous bromine

(e) describe the properties of alkenes (exemplified by ethene) in terms of combustion, polymerisation and the addition reactions with bromine, steam and hydrogen

(f) state the meaning of polyunsaturated when applied to food products

(g) describe the manufacture of margarine by the addition of hydrogen to unsaturated vegetable oils to form a solid product.

11.4 Alcohols

(a) describe the alcohols as a homologous series containing the –OH group

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(b) draw the structures of alcohols, C1 to C4, and name the unbranched alcohols methanol to butanol

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(c) describe the properties of alcohols in terms of combustion and oxidation to carboxylic acids

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(d) describe the formation of ethanol by:

(i) the fermentation of glucose.

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(d) describe the formation of ethanol by:

(ii) the catalysed addition of steam to ethene.

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(e) state some uses of ethanol, e.g. as a solvent; as a fuel; as a constituent of alcoholic beverages.

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11.5 Carboxylic acids

(a) describe the carboxylic acids as a homologous series containing the –CO2H group

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(b) draw the structures of carboxylic acids, methanoic acid to butanoic acid, and name the unbranched acids, methanoic acid to butanoic acid

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(c) describe the carboxylic acids as weak acids, reacting with carbonates, bases and some metals

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(d) describe the formation of ethanoic acid by the oxidation of ethanol by atmospheric oxygen or acidified potassium manganate(VII)

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(e) describe the reaction of a carboxylic acid with an alcohol to form an ester, e.g. ethyl ethanoate

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(f) state some commercial uses of esters, e.g. perfumes; flavourings; solvents.

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11.6 Macromolecules

(a) describe macromolecules as large molecules built up from small units, different macromolecules having different units and/or different linkages

(b) describe the formation of poly(ethene) as an example of addition polymerisation of ethene as the monomer

(c) state some uses of poly(ethene) as a typical plastic, e.g. plastic bags; clingfilm

(d) deduce the structure of the polymer product from a given monomer and vice versa

(e) describe nylon, a polyamide, and Terylene, a polyester, as condensation polymers, the partial structure of nylon being represented as

(Details of manufacture and mechanisms of these polymerisations are not required.)

(f) state some typical uses of man-made fibres such as nylon and Terylene, e.g. clothing; curtain materials; fishing line; parachutes; sleeping bags

(g) describe the pollution problems caused by the disposal of non-biodegradable plastics.