Atomic structure and the Periodic Table
2.2What the syllabus asks of you
- Describe the structure of the atom as a central nucleus containing neutrons and protons surrounded by electrons in shells
- State the relative charges and relative masses of a proton, a neutron and an electron
- Define proton number / atomic number as the number of protons in the nucleus of an atom
- Define mass number / nucleon number as the total number of protons and neutrons in the nucleus of an atom
- Determine the electronic configuration of elements and their ions with proton number 1 to 20, e.g. 2,8,3
- State that: (a) Group VIII noble gases have a full outer electron shell (b) the number of outer shell electrons is equal to the group number in Groups I to VII (c) the number of occupied electron shells is equal to the period number
Read the notes first
Chapter 2: Atomic structure and the Periodic Table
Drill this topic
Every question on Atomic structure and the Periodic Table, untimed, marked as you go.
Make a worksheet
Choose the years and how many questions, then print it with the answers on separate pages.
40 questions
1May / June 2026 · Paper 11 · Q4Show mark scheme →
Ahydrogen atom: both ○ and ●; hydrogen ion: both ○ and ●
Bhydrogen atom: both ○ and ●; hydrogen ion: ○ but not ●
Chydrogen atom: ● but not ○; hydrogen ion: neither ○ nor ●
Dhydrogen atom: ○ but not ●; hydrogen ion: ● but not ○
Mark scheme
2Oct / Nov 2025 · Paper 12 · Q3Show mark scheme →
AAtom X contains two more electrons than atom Y.
BAtom X contains three more neutrons than atom Y.
CAtom Y contains one more neutron than atom X.
DX and Y are atoms of the same element.
Mark scheme
3May / June 2025 · Paper 11 · Q3Show mark scheme →
Aberyllium
Bboron
Ccarbon
Dmagnesium
Mark scheme
4May / June 2025 · Paper 12 · Q4Show mark scheme →
AAn atom of Q has only two occupied electron shells.
BQ is a non-metal.
CThe atomic number of Q is 10.
DThe mass number of Q is greater than 24.
Mark scheme
5May / June 2025 · Paper 12 · Q5Also set in Oct / Nov 2018 Paper 12Show mark scheme →
AMg²⁺
BN³⁻
CNe
DS²⁻
Mark scheme
6Oct / Nov 2024 · Paper 11 · Q4Show mark scheme →
A16
B18
C19
D20
Mark scheme
7Oct / Nov 2024 · Paper 12 · Q3Show mark scheme →
A$^{15}_{28}\text{Z}$
B$^{26}_{13}\text{Z}$
C$^{28}_{13}\text{Z}$
D$^{28}_{15}\text{Z}$
Mark scheme
8May / June 2024 · Paper 11 · Q3Show mark scheme →
A17 | 7
B17 | 8
C20 | 7
D20 | 8
Mark scheme
9May / June 2024 · Paper 12 · Q3Show mark scheme →
Aone electron and one neutron
Bone electron and one proton
Cone neutron and one proton
Dtwo neutrons
Mark scheme
10Oct / Nov 2023 · Paper 11 · Q5Show mark scheme →
A1, 2 and 3
B1 and 2 only
C1 and 3 only
D2 and 3 only
Mark scheme
11May / June 2023 · Paper 11 · Q2Show mark scheme →
A2,4 2,7 2,8,4
B2,4 2,7 2,8,7
C2,4 2,8,4 2,8,7
D2,8,4 2,8,7 2,4
Mark scheme
12May / June 2023 · Paper 12 · Q2Show mark scheme →
AGroup III
BGroup V
CPeriod 4
DPeriod 5
Mark scheme
13Oct / Nov 2022 · Paper 11 · Q5Show mark scheme →
Aproton number of Q: 12, relative atomic mass of R: 35.5
Bproton number of Q: 12, relative atomic mass of R: 80
Cproton number of Q: 56, relative atomic mass of R: 80
Dproton number of Q: 56, relative atomic mass of R: 35.5
Mark scheme
14Oct / Nov 2022 · Paper 12 · Q6Also set in Oct / Nov 2022 Paper 11Show mark scheme →
AThey are both isotopes of iodine.
BThey undergo the same chemical reactions.
CThey have the same number of protons.
DThey have the same physical properties.
Mark scheme
15Oct / Nov 2022 · Paper 12 · Q8Also set in Oct / Nov 2022 Paper 11Show mark scheme →
A92
B143
C235
D327
Mark scheme
16May / June 2022 · Paper 11 · Q6Show mark scheme →
AThey contain the same number of electrons.
BThey contain the same number of neutrons.
CThey contain the same number of protons.
DThey do not contain the same number of protons, neutrons or electrons.
Mark scheme
17Oct / Nov 2021 · Paper 11 · Q8Show mark scheme →
AAtoms and ions of the same element must have different numbers of neutrons.
BIsotopes of different elements must have different numbers of neutrons.
CThe charge on a positive ion = (nucleon number – number of neutrons – number of electrons).
DThe number of protons and number of neutrons in an atom must be the same.
Mark scheme
18Oct / Nov 2021 · Paper 12 · Q8Show mark scheme →
AW 10, X 10, Y 12
BW 11, X 12, Y 10
CW 12, X 10, Y 12
DW 12, X 10, Y 10
Mark scheme
19May / June 2021 · Paper 11 · Q6Show mark scheme →
AO3–
BNe
CNa–
DMg3+
Mark scheme
20May / June 2021 · Paper 11 · Q27Show mark scheme →
AIons of X are negatively charged.
BAtoms of X have more electron shells than atoms of Y.
CX and Y are in the same period of the Periodic Table.
DX and Y are in the same group of the Periodic Table.
Mark scheme
21May / June 2021 · Paper 12 · Q7Show mark scheme →
AAr and Ca
BNa+ and K+
CFe2+ and Fe3+
DCa2+ and Sc3+
Mark scheme
22Oct / Nov 2020 · Paper 11 · Q8Show mark scheme →
AIt has 9 protons.
BIt has 10 protons.
CIt has 11 protons
DYou cannot deduce the number of protons from this diagram.
Mark scheme
23Oct / Nov 2020 · Paper 12 · Q8Show mark scheme →
Aaluminium
Bcalcium
Ciron
Dvanadium
Mark scheme
24Oct / Nov 2020 · Paper 12 · Q27Also set in Oct / Nov 2020 Paper 11Show mark scheme →
Acalcium
Bkrypton
Crubidium
Dselenium
Mark scheme
25May / June 2020 · Paper 12 · Q7Show mark scheme →
AH: both ○ and ●; H+: both ○ and ●
BH: both ○ and ●; H+: ○ but not ●
CH: ● but not ○; H+: neither ○ nor ●
DH: ○ but not ●; H+: ● but not ○
Mark scheme
26May / June 2020 · Paper 12 · Q8Also set in May / June 2020 Paper 11Show mark scheme →
AAl3+
BBe2+
CN3–
DS2–
Mark scheme
27May / June 2019 · Paper 11 · Q5Show mark scheme →
AIt is a 3+ ion.
BIt is a 3– ion.
CIt contains 24 neutrons.
DIt contains 24 protons.
Mark scheme
28May / June 2019 · Paper 12 · Q5Show mark scheme →
AAr has more neutrons than K$^+$.
BK has more nucleons than Ar.
CK$^+$ has 20 electrons.
DK$^+$ has a greater mass than Ar.
Mark scheme
29May / June 2019 · Paper 12 · Q27Also set in May / June 2019 Paper 11Show mark scheme →
ATheir atoms all have more neutrons than protons.
BTheir ions all have eight electrons in their outer shell.
CThey all sink when added to water.
DThey are all deposited at the positive electrode when their molten chloride is electrolysed.
Mark scheme
30May / June 2019 · Paper 12 · Q29Also set in May / June 2019 Paper 11Show mark scheme →
AThey are in the same group.
BThey are in the same period.
CThey are noble gases.
DThey are transition elements.
Mark scheme
31Oct / Nov 2018 · Paper 11 · Q5Show mark scheme →
Aprotons 16, neutrons 16, electrons 16
Bprotons 16, neutrons 18, electrons 18
Cprotons 18, neutrons 16, electrons 20
Dprotons 20, neutrons 14, electrons 22
Mark scheme
32May / June 2018 · Paper 11 · Q5Show mark scheme →
Acalcium
Bmagnesium
Coxygen
Dsulfur
Mark scheme
33May / June 2018 · Paper 12 · Q5Show mark scheme →
A58 protons, 82 neutrons, 54 electrons
B58 protons, 82 neutrons, 62 electrons
C82 protons, 58 neutrons, 54 electrons
D82 protons, 58 neutrons, 62 electrons
Mark scheme
34Oct / Nov 2017 · Paper 12 · Q6Show mark scheme →
A$^{40}_{20}\text{Ca}^{2+}$
B$^{24}_{12}\text{Mg}^{2+}$
C$^{19}_{9}\text{F}^{-}$
D$^{32}_{16}\text{S}^{2-}$
Mark scheme
35May / June 2017 · Paper 12 · Q4Also set in May / June 2017 Paper 11Show mark scheme →
AThey all contain more electrons than protons.
BThey all contain more neutrons than protons.
CThey all contain the same number of electrons.
DThey all contain the same number of protons.
Mark scheme
36May / June 2017 · Paper 12 · Q8Show mark scheme →
A1, 2 and 3
B1 and 2 only
C1 and 3 only
D2 and 3 only
Mark scheme
37Oct / Nov 2016 · Paper 11 · Q1Show mark scheme →
Anumber of neutrons plus protons
Bnumber of neutrons only
Cnumber of protons plus electrons
Dnumber of protons only
Mark scheme
38Oct / Nov 2016 · Paper 12 · Q6Also set in Oct / Nov 2016 Paper 11Show mark scheme →
AThey are both isotopes of chlorine.
BThey undergo the same chemical reactions.
CThey have the same number of protons.
DThey have the same physical properties.
Mark scheme
39May / June 2016 · Paper 11 · Q5Show mark scheme →
AThe fluoride ion contains more electrons than the sodium ion.
BThe sodium ion contains more neutrons than the fluoride ion.
CThe two ions contain the same number of electrons as each other.
DThe two ions contain the same number of protons as each other.
Mark scheme
40May / June 2016 · Paper 12 · Q25Show mark scheme →
AIt forms an ion with two negative charges.
BIt has a full outer shell of electrons.
CIt is a metal.
DIt is in Group VIII of the Periodic Table.
Mark scheme