Note:

IGCSE Chemistry Notes  Organic Chemistry  2023/2024/2025/2026/2027/2028

Syllabus Content:

11.1 Formulae, functional groups and terminology Core 1 Draw and interpret the displayed formula of a molecule to show all the atoms and all the bonds 2 Write and interpret general formulae of compounds in the same homologous series, limited to: (a) alkanes, CnH2n+2 (b) alkenes, CnH2n (c) alcohols, CnH2n+1OH (d) carboxylic acids, CnH2n+1COOH 3 Identify a functional group as an atom or group of atoms that determine the chemical properties of a homologous series Supplement 7 State that a structural formula is an unambiguous description of the way the atoms in a molecule are arranged, including CH2=CH2, CH3CH2OH, CH3COOCH3 8 Define structural isomers as compounds with the same molecular formula, but different structural formulae

11.1 Formulae, functional groups and terminology continued Core 4 State that a homologous series is a family of similar compounds with similar chemical properties due to the presence of the same functional group 5 State that a saturated compound has molecules in which all carbon–carbon bonds are single bonds 6 State that an unsaturated compound has molecules in which one or more carbon– carbon bonds are not single bonds Supplement 9 Describe the general characteristics of a homologous series as: (a) having the same functional group (b) having the same general formula (c) differing from one member to the next by a –CH2– unit (d) displaying a trend in physical properties (e) sharing similar chemical properties

11.2 Naming organic compounds Core 1 Name and draw the displayed formulae of: (a) methane and ethane (b) ethene (c) ethanol (d) ethanoic acid (e) the products of the reactions stated in sections 11.4–11.7 2 State the type of compound present, given a chemical name ending in -ane, -ene, -ol, or -oic acid or from a molecular formula or displayed formula Supplement 3 Name and draw the structural and displayed formulae of unbranched: (a) alkanes (b) alkenes, including but-1-ene and but-2-ene (c) alcohols, including propan-1-ol, propan-2-ol, butan-1-ol and butan-2-ol (d) carboxylic acids containing up to four carbon atoms per molecule 4 Name and draw the displayed formulae of the unbranched esters which can be made from unbranched alcohols and carboxylic acids, each containing up to four carbon atoms

11.3 Fuels Core 1 Name the fossil fuels: coal, natural gas and petroleum 2 Name methane as the main constituent of natural gas 3 State that hydrocarbons are compounds that contain hydrogen and carbon only 4 State that petroleum is a mixture of hydrocarbons 5 Describe the separation of petroleum into useful fractions by fractional distillation 6 Describe how the properties of fractions obtained from petroleum change from the bottom to the top of the fractionating column, limited to: (a) decreasing chain length (b) higher volatility (c) lower boiling points (d) lower viscosity 7 Name the uses of the fractions as: (a) refinery gas fraction for gas used in heating and cooking (b) gasoline/petrol fraction for fuel used in cars (c) naphtha fraction as a chemical feedstock (d) kerosene/paraffin fraction for jet fuel (e) diesel oil/gas oil fraction for fuel used in diesel engines (f) fuel oil fraction for fuel used in ships and home heating systems (g) lubricating oil fraction for lubricants, waxes and polishes (h) bitumen fraction for making roads

11.4 Alkanes Core 1 State that the bonding in alkanes is single covalent and that alkanes are saturated hydrocarbons 2 Describe the properties of alkanes as being generally unreactive, except in terms of combustion and substitution by chlorine Supplement 3 State that in a substitution reaction one atom or group of atoms is replaced by another atom or group of atoms 4 Describe the substitution reaction of alkanes with chlorine as a photochemical reaction, with ultraviolet light providing the activation energy, Ea, and draw the structural or displayed formulae of the products, limited to monosubstitution 11.5 Alkenes Core 1 State that the bonding in alkenes includes a double carbon–carbon covalent bond and that alkenes are unsaturated hydrocarbons 2 Describe the manufacture of alkenes and hydrogen by the cracking of larger alkane molecules using a high temperature and a catalyst 3 Describe the reasons for the cracking of larger alkane molecules 4 Describe the test to distinguish between saturated and unsaturated hydrocarbons by their reaction with aqueous bromine Supplement 5 State that in an addition reaction only one product is formed 6 Describe the properties of alkenes in terms of addition reactions with: (a) bromine or aqueous bromine (b) hydrogen in the presence of a nickel catalyst (c) steam in the presence of an acid catalyst and draw the structural or displayed formulae of the products

11.6 Alcohols Core 1 Describe the manufacture of ethanol by: (a) fermentation of aqueous glucose at 25– 35°C in the presence of yeast and in the absence of oxygen (b) catalytic addition of steam to ethene at 300°C and 6000kPa/60 atm in the presence of an acid catalyst 2 Describe the combustion of ethanol 3 State the uses of ethanol as: (a) a solvent (b) a fuel Supplement 4 Describe the advantages and disadvantages of the manufacture of ethanol by: (a) fermentation (b) catalytic addition of steam to ethene 11.7 Carboxylic acids Core 1 Describe the reaction of ethanoic acid with: (a) metals (b) bases (c) carbonates including names and formulae of the salts produced Supplement 2 Describe the formation of ethanoic acid by the oxidation of ethanol: (a) with acidified aqueous potassium manganate(VII) (b) by bacterial oxidation during vinegar production 3 Describe the reaction of a carboxylic acid with an alcohol using an acid catalyst to form an ester

11.8 Polymers Core 1 Define polymers as large molecules built up from many smaller molecules called monomers 2 Describe the formation of poly(ethene) as an example of addition polymerisation using ethene monomers 3 State that plastics are made from polymers 4 Describe how the properties of plastics have implications for their disposal 5 Describe the environmental challenges caused by plastics, limited to: (a) disposal in landfill sites (b) accumulation in oceans (c) formation of toxic gases from burning Supplement 6 Identify the repeat units and/or linkages in addition polymers and in condensation polymers 7 Deduce the structure or repeat unit of an addition polymer from a given alkene and vice versa 8 Deduce the structure or repeat unit of a condensation polymer from given monomers and vice versa, limited to: (a) polyamides from a dicarboxylic acid and a diamine (b) polyesters from a dicarboxylic acid and a diol 9 Describe the differences between addition and condensation polymerisation 10 Describe and draw the structure of: (a) nylon, a polyamide

The full name for PET, polyethylene terephthalate, is not required 11 State that PET can be converted back into monomers and re-polymerised 12 Describe proteins as natural polyamides and that they are formed from amino acid monomers with the general structure:

3 Describe and draw the structure of proteins