Formulae, functional groups and terminology
11.1What the syllabus asks of you
- State that a structural formula is an unambiguous description of the way the atoms in a molecule are arranged, including CH2=CH2, CH3CH2OH, CH3COOCH3
- Draw and interpret the displayed formula of a molecule to show all the atoms and all the bonds
- 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
- Define structural isomers as compounds with the same molecular formula, but different structural formulae, including C4H10 as CH3CH2CH2CH3 and CH3CH(CH3)CH3 and C4H8 as CH3CH2CH=CH2 and CH3CH=CHCH3
- Identify a functional group as an atom or group of atoms that determine the chemical properties of a homologous series
- 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
- State that a saturated compound has molecules in which all carbon–carbon bonds are single bonds
- State that an unsaturated compound has molecules in which one or more carbon–carbon bonds are not single bonds
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Chapter 11: Formulae, functional groups and terminology
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39 questions
1May / June 2026 · Paper 11 · Q31Show mark scheme →
A1, 2 and 3
B1 and 2 only
C1 only
D2 and 3 only
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2May / June 2026 · Paper 12 · Q31Show mark scheme →
A1, 2 and 3
B1 and 2 only
C1 and 3 only
D2 and 3 only
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3Oct / Nov 2025 · Paper 11 · Q30Show mark scheme →
A2
B3
C4
D5
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4Oct / Nov 2025 · Paper 11 · Q31Show mark scheme →
AH-C(=C)-C-H structural formula (but-2-ene type structure)
BH-C-C(=C)-C-H structural formula (methylpropene type structure)
CH-C-C-C-H with methyl branch structural formula (2-methylpropane type structure)
DH-C=C-C-C-H structural formula (pent-2-ene type structure)
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5Oct / Nov 2025 · Paper 12 · Q31Show mark scheme →
A1 2
B2 2
C2 3
D1 3
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6May / June 2025 · Paper 11 · Q32Also set in Oct / Nov 2019 Paper 12Show mark scheme →
ACH3-CH(OH)-CH2-CH3 (butan-2-ol)
BCH2(OH)-CH2-CH2-CH2(OH) (butane-1,4-diol)
CCH3-CH2-COOH (propanoic acid)
DCH3-CH2-CO-CH3 (butanone)
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7May / June 2025 · Paper 12 · Q32Show mark scheme →
A2
B3
C4
D5
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8Oct / Nov 2024 · Paper 11 · Q31Show mark scheme →
Astructure A
Bstructure B
Cstructure C
Dstructure D
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9May / June 2024 · Paper 11 · Q33Show mark scheme →
A1 and 2
B1 and 4
C2 and 3
D2 and 4
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10May / June 2024 · Paper 12 · Q32Show mark scheme →
AAn unsaturated hydrocarbon is one in which more solute can dissolve.
BMembers of a homologous series each differ from the next by a –CH2– unit.
CStructural isomers have the same displayed formula but different structural formulae.
DThe general formula of the carboxylic acid homologous series is CnH2nCOOH.
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11Oct / Nov 2023 · Paper 11 · Q32Show mark scheme →
ACH3CH2CH2CH3, CH3CHCHCH3 and CH3CH(CH3)CH3
BCH2CHCH3, CH3CH2CHCH2 and CH2CHCH2CH3
CCH3CHOHCH3, CH3CH2CH2OH and CH3CH2COOH
DCH3CH2CH3, CH3CH2CH2CH3 and CH2CHCH2CH2CH3
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12Oct / Nov 2023 · Paper 11 · Q33Show mark scheme →
A1 and 2
B1 and 3
C2 and 3
D2 and 4
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13Oct / Nov 2023 · Paper 11 · Q38Show mark scheme →
A1, 2 and 3
B1 only
C2 and 3 only
D3 and 4
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14Oct / Nov 2023 · Paper 12 · Q33Show mark scheme →
AEach molecule of propan-1-ol has one –OH group and each molecule of propan-2-ol has two –OH groups.
BOctane and decane are in a homologous series with the general formula CnH2n.
CThe ester butyl butanoate has eight carbon atoms in each molecule.
DThe structure of the functional group in a carboxylic acid is –C–O–O–H.
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15Oct / Nov 2023 · Paper 12 · Q35Show mark scheme →
A1
B2
C3
D4
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16May / June 2023 · Paper 11 · Q33Show mark scheme →
A1 and 2 only
B1 and 3 only
C2 and 3 only
D1, 2 and 3
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17May / June 2022 · Paper 11 · Q34Show mark scheme →
Aboth statement 1 and statement 2
Bstatement 1 only
Cstatement 2 only
Dneither statement 1 nor statement 2
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18Oct / Nov 2021 · Paper 12 · Q36Show mark scheme →
A1, 2 and 3
B1 and 3 only
C1 only
D2 and 3 only
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19Oct / Nov 2021 · Paper 12 · Q38Show mark scheme →
AH-C(H)(H)-C(H)(H)-O-C(H)(H)-H
BH-C(H)(H)-C(H)(H)-C(H)(H)-O-H
CH-C(H)(H)-C(H)(H)-C(H)(H)-O-H (epoxide ring)
DH-C(H)(H)-C(H)(H)-C(=O)-O-H
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20May / June 2021 · Paper 12 · Q38Show mark scheme →
Astructure A
Bstructure B
Cstructure C
Dstructure D
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21Oct / Nov 2020 · Paper 11 · Q36Show mark scheme →
AH-C(H)=C(H)-C(H)(H)-C(H)(H)-H (but-2-ene, straight chain)
BH-C(H)(H)-C(H)(C(H)(H)(H))-C(H)(H)-H (methylpropane derivative)
CH-C(H)(H)-C(H)(H)-C(H)(H)-C(H)(H)(H) (butane)
DH-C(H)(H)-C(H)=C(H)-C(H)(H)-C(H)(H)(H) (pent-2-ene)
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22May / June 2020 · Paper 11 · Q33Show mark scheme →
Asaturated carboxylic acid
Bsaturated ester
Cunsaturated carboxylic acid
Dunsaturated ester
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23May / June 2020 · Paper 12 · Q33Show mark scheme →
AH-C-H with H-C-C-C-H chain structure
Bbranched structure with H-C-C and H-C-H
CH-C-H with H-C-C-C-H chain structure
DH-C-C-H with H-C-C-H structure
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24May / June 2020 · Paper 12 · Q34Show mark scheme →
AOnly C2H4 and C2H6 decolourise bromine water.
BThey are all saturated compounds.
CThey are all unsaturated compounds.
DThey are all hydrocarbons.
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25Oct / Nov 2019 · Paper 11 · Q8Show mark scheme →
ACH2 empirical formula, C2H4 molecular formula, CnH2n general formula
BCH2 empirical formula, C2H4 general formula, CnH2n molecular formula
CCH2 general formula, C2H4 molecular formula, CnH2n empirical formula
DCH2 molecular formula, C2H4 empirical formula, CnH2n general formula
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26Oct / Nov 2019 · Paper 11 · Q32Show mark scheme →
A1, 2, 3 and 4
B1, 2, and 3 only
C1 and 4 only
D3 and 4 only
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27Oct / Nov 2019 · Paper 11 · Q35Show mark scheme →
A2
B3
C4
D5
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28Oct / Nov 2019 · Paper 12 · Q33Also set in Oct / Nov 2019 Paper 11Show mark scheme →
A1 and 2
B1 and 4
C2 and 3
D2 and 4
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29Oct / Nov 2018 · Paper 11 · Q34Show mark scheme →
A1
B2
C3
D4
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30Oct / Nov 2018 · Paper 11 · Q37Show mark scheme →
AC=C
BCO2H
CCONH
DOH
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31May / June 2018 · Paper 11 · Q36Show mark scheme →
AC31H33
BC31H60
CC31H62
DC31H64
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32May / June 2018 · Paper 12 · Q36Show mark scheme →
AH-C(H)(H)-C(H)(C(H)(H)(H))-C(H)(H)-H
BH-C(H)(H)-C(H)(H)-C(H)(H)-C(H)(H)-H
CH-C(H)(H)-C(H)(H)-C(H)(H)-C(H)(H)-H
DH-C(H)(H)-C(H)(C(H)(H)(H))-C(H)(H)-H
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33Oct / Nov 2017 · Paper 12 · Q37Show mark scheme →
A1, 2 and 4
B2, 3 and 5
C2, 3 and 4
D3, 4 and 5
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34May / June 2017 · Paper 12 · Q36Show mark scheme →
AX is an alcohol because it contains an –OH group.
BX is an isomer of propanol.
CX would burn in air to form carbon dioxide and water.
DX would have a higher boiling point than ethanol.
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35May / June 2017 · Paper 12 · Q38Show mark scheme →
Aalkane: 1 and 2; alkene: 3 and 4
Balkane: 1 and 3; alkene: 2 and 4
Calkane: 1 and 4; alkene: 2 and 3
Dalkane: 2 and 3; alkene: 1 and 4
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36Oct / Nov 2016 · Paper 11 · Q36Show mark scheme →
Aboth 1 and 2
B1 only
C2 only
Dneither 1 nor 2
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37Oct / Nov 2016 · Paper 11 · Q39Show mark scheme →
AIt undergoes addition reactions with chlorine.
BIt has a lower boiling point than methane.
CIt has the same general formula as methane.
DThere are four C–C bonds in the molecule.
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38Oct / Nov 2016 · Paper 12 · Q38Show mark scheme →
AThey have different empirical formulae.
BThey have different relative molecular masses.
CThey have only carbon and hydrogen in their molecules.
DThey have the same molecular formula.
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39May / June 2016 · Paper 12 · Q40Show mark scheme →
Aisomers of each other: W and X; decolourise bromine: Y and Z; branched structures: W and Y
Bisomers of each other: W and X; decolourise bromine: Y and Z; branched structures: X and Z
Cisomers of each other: Y and Z; decolourise bromine: W and Y; branched structures: X and Z
Disomers of each other: Y and Z; decolourise bromine: W and Z; branched structures: W and Y
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