Simple molecules and covalent bonds
2.5What the syllabus asks of you
- State that a covalent bond is formed when a pair of electrons is shared between two atoms leading to noble gas electronic configurations
- Describe the formation of covalent bonds in simple molecules, including H2, Cl2, H2O, CH4, NH3, HCl, CH3OH, C2H4, O2, CO2 and N2. Use dot-and-cross diagrams to show the electronic configurations in these and similar molecules
- Describe and explain in terms of structure and bonding the properties of simple molecular compounds: (a) low melting points and boiling points in terms of weak intermolecular forces (specific types of intermolecular forces are not required) (b) poor electrical conductivity
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Chapter 2: Simple molecules and covalent bonds
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Every question on Simple molecules and covalent bonds, untimed, marked as you go.
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Choose the years and how many questions, then print it with the answers on separate pages.
35 questions
1Oct / Nov 2025 · Paper 11 · Q4Show mark scheme →
A14, 8
B14, 6
C18, 8
D18, 6
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2Oct / Nov 2025 · Paper 12 · Q6Show mark scheme →
Agiant covalent / giant covalent
Bgiant covalent / simple molecular
Csimple molecular / giant covalent
Dsimple molecular / simple molecular
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3Oct / Nov 2024 · Paper 11 · Q6Show mark scheme →
ACH3OH and C2H4
BCO2 and H2O
CNH3 and N2
DO2 and Cl2
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4Oct / Nov 2024 · Paper 12 · Q2Show mark scheme →
AX could be: an element only; Y could be: an element only
BX could be: an element only; Y could be: an element or a compound
CX could be: an element or a compound; Y could be: an element only
DX could be: an element or a compound; Y could be: an element or a compound
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5May / June 2024 · Paper 11 · Q16Show mark scheme →
Achemical; intermolecular forces break
Bchemical; Si–Cl covalent bonds break
Cphysical; intermolecular forces break
Dphysical; Si–Cl covalent bonds break
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6May / June 2024 · Paper 12 · Q5Show mark scheme →
ACl$_2$
BCO$_2$
CH$_2$S
DN$_2$
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7May / June 2023 · Paper 11 · Q5Show mark scheme →
A1, 2 and 3
B1 and 2 only
C1 and 3 only
D2 and 3 only
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8May / June 2023 · Paper 12 · Q5Show mark scheme →
AC2H4
BCO2
CCH3OH
DN2
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9Oct / Nov 2022 · Paper 11 · Q11Show mark scheme →
ACH3CH3
BCH3CH2OH
CCH3CO2H
DCH3CHCH2
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10Oct / Nov 2022 · Paper 12 · Q10Show mark scheme →
Athe two carbon atoms in a $\mathrm{C_2H_4}$ molecule; the carbon atom and one oxygen atom in a $\mathrm{CO_2}$ molecule
Bthe two nitrogen atoms in an $\mathrm{N_2}$ molecule; the two hydrogen atoms in an $\mathrm{H_2}$ molecule
Cthe two oxygen atoms in an $\mathrm{O_2}$ molecule; the carbon atom and one hydrogen atom in a $\mathrm{CH_4}$ molecule
Dthe two oxygen atoms in an $\mathrm{O_2}$ molecule; the two nitrogen atoms in an $\mathrm{N_2}$ molecule
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11Oct / Nov 2022 · Paper 12 · Q11Show mark scheme →
AIt is unusual for a non-metal such as fluorine to form covalent bonds.
BThe boron atom in each molecule does not gain the electronic configuration of a noble gas.
CThe covalent bonds do not consist of shared pairs of electrons.
DThe fluorine atoms in each molecule do not gain the electronic configuration of a noble gas.
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12May / June 2022 · Paper 11 · Q8Show mark scheme →
AW and X conduct electricity.
BW and Y are elements.
CX and Z dissolve in water.
DY and Z have low melting points.
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13May / June 2022 · Paper 11 · Q10Show mark scheme →
AO C O with dot-and-cross diagram
BO C O with dot-and-cross diagram
CO C O with dot-and-cross diagram
DO C O with dot-and-cross diagram
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14May / June 2022 · Paper 12 · Q10Show mark scheme →
AEach molecule of SiF4 has exactly 16 pairs of electrons.
BIn SiF4 both the silicon and the fluorine have the same electronic configuration as neon.
CMolten SiF4 will conduct electricity.
DSiF4 has a low melting point.
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15Oct / Nov 2021 · Paper 11 · Q9Show mark scheme →
AO=C=O (diagram A)
BO=C=O (diagram B)
CC=O=C (diagram C)
DO=C=O (diagram D)
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16Oct / Nov 2021 · Paper 12 · Q27Also set in Oct / Nov 2021 Paper 11, Oct / Nov 2018 Paper 12Show mark scheme →
AW and X
BW and Y
CX and Y
DY and Z
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17May / June 2021 · Paper 11 · Q8Show mark scheme →
Aa pair of electrons shared by two non-metallic atoms
Belectrons being shared by a lattice of positively charged ions
Celements losing electrons to achieve a noble gas structure
Doppositely charged particles strongly attracting each other
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18May / June 2021 · Paper 12 · Q9Show mark scheme →
A
B
C
D
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19Oct / Nov 2020 · Paper 11 · Q12Show mark scheme →
AX = 14, Y = 12
BX = 14, Y = 14
CX = 18, Y = 12
DX = 18, Y = 14
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20Oct / Nov 2020 · Paper 12 · Q12Show mark scheme →
A1, 2 and 3
B2, 3 and 4
C1, 2 and 4
D1, 3 and 4
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21May / June 2020 · Paper 11 · Q11Show mark scheme →
ADiagram A (CH4)
BDiagram B (C2H4)
CDiagram C (CO2)
DDiagram D (HCl)
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22May / June 2020 · Paper 12 · Q11Show mark scheme →
A2
B4
C8
D12
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23Oct / Nov 2019 · Paper 12 · Q4Also set in Oct / Nov 2019 Paper 11Show mark scheme →
Ahydrogen, oxygen, helium
Bnitrogen, chlorine, neon
Cnitrogen, oxygen, fluorine
Doxygen, chlorine, helium
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24May / June 2019 · Paper 11 · Q8Show mark scheme →
A3
B4
C5
D6
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25May / June 2019 · Paper 12 · Q8Show mark scheme →
A2
B4
C8
D12
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26Oct / Nov 2018 · Paper 11 · Q8Show mark scheme →
Adot-and-cross diagram A
Bdot-and-cross diagram B
Cdot-and-cross diagram C
Ddot-and-cross diagram D
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27May / June 2018 · Paper 12 · Q8Also set in May / June 2018 Paper 11Show mark scheme →
A1, 2 and 3
B1 and 2 only
C1 and 3 only
D2 and 3 only
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28May / June 2017 · Paper 12 · Q7Also set in May / June 2017 Paper 11Show mark scheme →
A2
B3
C4
D5
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29May / June 2017 · Paper 12 · Q8Show mark scheme →
A1, 2 and 3
B1 and 2 only
C1 and 3 only
D2 and 3 only
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30Oct / Nov 2016 · Paper 11 · Q5Show mark scheme →
A1 and 3
B1 only
C2 and 3
D2 only
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31Oct / Nov 2016 · Paper 12 · Q7Show mark scheme →
A44, non-conductor
B98, conductor
C660, conductor
D714, non-conductor
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32Oct / Nov 2016 · Paper 12 · Q9Show mark scheme →
Aa covalent compound
Ban ionic compound
Ca polymer
Dmolecular
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33May / June 2016 · Paper 11 · Q6Show mark scheme →
AH H
BH Cl
CO C O
DH C H with H above and below
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34May / June 2016 · Paper 12 · Q8Show mark scheme →
AEthene is a liquid at room temperature and pressure.
BLiquid ethene conducts electricity.
COne ethene molecule contains sixteen protons.
DThe total number of shared pairs of electrons in ethene is five.
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35May / June 2016 · Paper 12 · Q16Show mark scheme →
AOil and water are immiscible.
BOil is less dense than water.
CSome molecules in oil have a higher relative molecular mass than water.
DThe type of bonding within water molecules is different from the type of bonding within molecules in oil.
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