Atomic structure: OCR GCSE Chemistry A questions

Every OCR GCSE Chemistry A exam question on C1.2 Atomic structure, 2018–2025, with its mark scheme and examiner’s report.

All 74 questions on Atomic structure, as a list

June 2025, Paper 1 Foundation, Q2 (1 mark): What is the part of the atom labelled X? X A Electron B Neutron C Nucleus D Proton Your answer [1]
June 2025, Paper 1 Foundation, Q3 (1 mark): What is the typical radius of an atom? 1 × 10–10 m A 1 × 10–1 m B 1 × 101 m C 1 × 1010 m D Your answer [1]
June 2025, Paper 1 Foundation, Q20(a) (3 marks): Table 20.1 shows some information about the subatomic particles. Table 20.1 Subatomic particle Relative mass Relative charge Electron Neutron 1 Proton +1 Comple
June 2025, Paper 1 Foundation, Q20(b) (2 marks): Fig. 20.1 shows some information about a lithium atom. Fig. 20.1 3 Li 7 lithium Which statements about this lithium atom are true, and which are false? Tick (✓)
June 2025, Paper 1 Foundation, Q20(d)(i) (3 marks): Lithium can exist as different isotopes. Complete the sentence about isotopes. Use words from the list. compound electrons element ion neutrons protons Isotopes
June 2025, Paper 1 Foundation, Q20(d)(ii) (2 marks): Table 20.2 shows information about two different isotopes of lithium. Table 20.2 Isotope Mass Number 6 Li 3 Li 7 Complete the table. [2]
June 2025, Paper 3 Higher, Q3 (1 mark): Which atomic model was developed by Thomson? A + – – + + + B –+ – – + – + C D Your answer [1]
June 2025, Paper 3 Higher, Q19(a) (3 marks): The table shows some information about the subatomic particles. Subatomic particle Relative mass Relative charge Electron Neutron 1 Proton 1 +1 Complete the tab
June 2025, Paper 3 Higher, Q19(c) (3 marks): Lithium exists as two isotopes. Complete the sentence about isotopes. Use words from the list. atom electrons element ion neutrons protons Isotopes are atoms of
June 2025, Paper 3 Higher, Q19(e) (3 marks): A sample of lithium is 11.5 cm wide. Estimate how many lithium atoms would fit across the width of the sample. Use your knowledge of the typical radius of atoms
June 2024, Paper 1 Foundation, Q1 (1 mark): Which part of an atom is negatively charged? A Electron B Neutron C Nucleus D Proton Your answer [1]
June 2024, Paper 1 Foundation, Q6 (1 mark): Which scientist suggested the idea that electrons exist in electron shells? A Bohr B Dalton C Rutherford D Thomson Your answer [1]
June 2024, Paper 1 Foundation, Q8 (1 mark): The table shows information about some atoms and ions. Which two are isotopes? Atom or ion Number of protons Number of neutrons Number of electrons 1 17 18 17 2
June 2024, Paper 1 Foundation, Q16(b)(i) (1 mark): How many protons does an oxygen atom have? [1]
June 2024, Paper 1 Foundation, Q16(b)(ii) (1 mark): How many neutrons does a hydrogen atom have? [1]
June 2024, Paper 1 Foundation, Q16(b)(iii) (1 mark): What is the relative charge of a proton? [1]
June 2024, Paper 1 Foundation, Q21(a) (1 mark): How many orders of magnitude larger is the diamond than the carbon atom? Tick (3) one box. Two Four Seven [1]
June 2024, Paper 1 Foundation, Q21(b) (3 marks): Calculate the number of carbon atoms that fit in the width of the diamond. Give your answer in standard form to 1 decimal place. Number of carbon atoms = [3]
June 2024, Paper 3 Higher, Q19(a) (2 marks): Describe two ways Rutherford’s atomic model was an improvement on Thomson’s “plum pudding” atomic model. 1 2 [2]
June 2024, Paper 3 Higher, Q19(b)(ii) (2 marks): The table shows information about three different ions. Complete the table. Number of Number of Number of Ion Mass number protons neutrons electrons Mg2+ 12 10
June 2024, Paper 3 Higher, Q19(b)(iii) (2 marks): The element lithium exists as isotopes. State one difference and one similarity between the Li+ ions formed from different isotopes of lithium. Difference Simil
June 2024, Paper 3 Higher, Q19(b)(iv) (3 marks): A sample of magnesium metal is 5.2 cm wide. Estimate how many Mg2+ ions would fit across the width of the sample of magnesium metal. Use your knowledge of the t
June 2023, Paper 1 Foundation, Q1 (1 mark): Where is most of the mass found in an atom? A Electrons B Neutrons C Nucleus D Protons Your answer [1]
June 2023, Paper 1 Foundation, Q4 (1 mark): Thomson discovered the first sub-atomic particle. Which sub-atomic particle did Thomson discover? A Atom B Electron C Neutron D Proton Your answer [1]
June 2023, Paper 1 Foundation, Q8 (1 mark): When the model of the atom was developed, scientists reviewed the work of other scientists. Why is it important for scientists to review each other’s work? A Th
June 2023, Paper 1 Foundation, Q16(b) (2 marks): Draw lines to connect each particle with its correct description. Particle Description proton relative mass of 0.0005 positively charged and electron relative m
June 2023, Paper 1 Foundation, Q16(c)(i) (1 mark): Which isotope has the highest mass? [1]
June 2023, Paper 1 Foundation, Q16(c)(ii) (1 mark): Which isotope has the same number of protons and neutrons? [1]
June 2023, Paper 1 Foundation, Q16(c)(iii) (1 mark): Atoms of each isotope have the same number of electrons. How many electrons do these atoms have? [1]
June 2023, Paper 1 Foundation, Q16(d) (2 marks): A sample of air contains all three isotopes of oxygen. It contains 99.759% of isotope 1 and 0.037% of isotope 2. Calculate the percentage of isotope 3 in the sa
June 2023, Paper 3 Higher, Q18(a) (3 marks): The model of the atom has developed over time. Describe the experiment and results that Rutherford, Geiger, and Marsden used to determine that an atom has a nuc
June 2023, Paper 3 Higher, Q18(b) (2 marks): Which statements about atoms are correct? Tick (3) two boxes. A proton has a positive charge and a relative mass of 1. An atomic radius is approximately 1 × 10–
June 2023, Paper 3 Higher, Q20(c)(i) (2 marks): Draw three lines to connect each isotope with its correct description. Isotope Description This isotope contains 17 neutrons. 16 S This isotope has a full outer
June 2022, Paper 1 Foundation, Q10 (1 mark): What did Rutherford suggest about the model of the atom? A Atoms contain a nucleus. B Atoms contain electrons. C The atom is a solid sphere like a billiard ball
June 2022, Paper 1 Foundation, Q16(a) (3 marks): Complete the sentences about the structure of an atom. Use words from the list. electrons negative neutral neutrons positive protons An atom has a nucleus with
June 2022, Paper 1 Foundation, Q16(b)(i) (2 marks): Look at the information about two isotopes of boron. 5 5 B B 10 11 Which statements about the isotopes of boron are correct? Tick (3) two boxes. Boron has 11 pr
June 2022, Paper 1 Foundation, Q16(b)(ii) (1 mark): The diagram shows a boron atom. xx xx B x Explain why boron is in Group 3 of the Periodic Table. [1]
June 2022, Paper 3 Higher, Q2 (1 mark): The radius of a helium atom is 0.14 nm. What is the radius of a helium atom in metres? 0.14 × 10–10 m A 1.4 × 10–10 m B 1.4 × 10–9 m C 14 × 10–9 m D Your answer
June 2022, Paper 3 Higher, Q4 (1 mark): The diagram of an atom shows that electrons occupy shells around the nucleus. Which scientist proposed this atomic model? A Bohr B Dalton C J. J. Thomson D Mend
November 2021, Paper 1 Foundation, Q1 (1 mark): Which of these particles has a positive charge? A Atom B Electron C Neutron D Proton Your answer [1]
November 2021, Paper 1 Foundation, Q5 (1 mark): What is the mass number of an atom? A The total number of neutrons and electrons in an atom. B The total number of protons and electrons in an atom. C The total
November 2021, Paper 3 Higher, Q1 (1 mark): Which statement about the subatomic particles in an atom is correct? A Electrons have a relative mass of one. B Neutrons and electrons are both found in the nuc
November 2021, Paper 3 Higher, Q4 (1 mark): Oxygen has three naturally occurring isotopes. Which statement about isotopes of oxygen is correct? A All isotopes of oxygen have 8 electrons and 8 neutrons. B
November 2021, Paper 3 Higher, Q15 (1 mark): A carbon dioxide molecule is shown in the ball and stick model. Which estimate of the distance between the oxygen atoms in a carbon dioxide molecule is correct?
November 2021, Paper 3 Higher, Q19(a)(i) (2 marks): Describe two differences between the current understanding of the structure of the atom and J.J. Thomson’s “plum pudding” model. 1 2 [2]
November 2021, Paper 3 Higher, Q19(a)(ii) (2 marks): Before new scientific theories are published, the theories are peer reviewed. Which statements about peer review are correct? Tick (✓) two boxes. A scientist gi
November 2021, Paper 3 Higher, Q19(b)(ii) (1 mark): Three isotopes of neon are shown. 20 21 22 Ne Ne Ne 10 10 10 How many neutrons does an atom of neon-21 contain? [1]
November 2020, Paper 1 Foundation, Q10 (1 mark): The diagram shows an atom of an element. Neutron Electron Proton What is the name of the element? A Boron B Beryllium C Fluorine D Neon Your answer [1]
November 2020, Paper 1 Foundation, Q12 (1 mark): A potassium isotope can be shown as: 3 9 9K 1 What are the numbers of protons, neutrons and electrons in this potassium isotope? A 19 protons, 19 neutrons, 20 e
November 2020, Paper 1 Foundation, Q23(d)(ii) (3 marks): Neon is an element that has isotopes. Two of the isotopes are shown below. 2 0 2 2 0 Ne 0 Ne 1 1 Complete Table 23.3 to show the number of protons, neutrons and
November 2020, Paper 3 Higher, Q5 (1 mark): Carbon-12 and carbon-14 are isotopes. Which statement describes isotopes? A Atoms with the same number of protons but a different number of electrons. B Atoms w
November 2020, Paper 3 Higher, Q6 (1 mark): The diagram shows an atom of an element. Neutron Electron Proton What is the name of the element? A Boron B Beryllium C Fluorine D Neon Your answer [1]
November 2020, Paper 3 Higher, Q7 (1 mark): The charge on an electron is −1.6 × 10−19 C. 7 What is the charge on a proton? −1.6 × 1019 C A −1.6 × 10−19 C B 1.6 × 10−19 C C 1.6 × 1019 C D Your answer [1]
November 2020, Paper 3 Higher, Q17(d)(ii) (3 marks): Neon is an element that has isotopes. Two of the isotopes are shown below. 2 0 2 2 0 Ne 0 Ne 1 1 Complete Table 17.3 to show the number of protons, neutrons and
June 2019, Paper 1 Foundation, Q10 (1 mark): In 1803 John Dalton suggested that all matter is made from atoms. The electron was the first subatomic particle to be discovered by J.J. Thomson in 1897. J.J. T
June 2019, Paper 1 Foundation, Q12 (1 mark): A sodium atom can be shown as: 23 11 Na How many protons, neutrons and electrons are in a sodium atom? A 11 protons, 12 neutrons, 11 electrons B 11 protons, 11
June 2019, Paper 1 Foundation, Q21(a)(i) (2 marks): Complete the labels on the diagram of an atom. X X X X X X Nucleus containing XX and [2]
June 2019, Paper 1 Foundation, Q21(a)(ii) (1 mark): Atoms have no overall charge. Explain why. Use ideas about subatomic particles in your answer. [1]
June 2019, Paper 1 Foundation, Q21(b) (2 marks): Look at the information about two isotopes of carbon. 12 14 C C 6 6 Explain why these are called isotopes. [2]
June 2019, Paper 3 Higher, Q7 (1 mark): The atomic radius of a helium atom is 0.031 nm. What is the atomic radius of a helium atom in standard form? 3.1 × 10−1 A 3.1 × 10−2 B 3.1 × 10−3 C 3.1 × 10−4 D
June 2019, Paper 3 Higher, Q8 (1 mark): What is the electronic structure of sulfur? A 2 B 2, 6 C 2, 8, 6 D 2, 8, 8, 6 Your answer [1]
June 2019, Paper 3 Higher, Q19(c)(i) (2 marks): Chlorine is a non-metal. Chlorine has two common isotopes. Look at the information about the common isotopes of chlorine. 35 37 Cl Cl 17 17 Complete the table t
June 2018, Paper 1 Foundation, Q3 (1 mark): A number of scientists contributed to the development of the atomic model. Which of these scientists discovered the electron? A Bohr B Dalton C Rutherford D Tho
June 2018, Paper 1 Foundation, Q5 (1 mark): What is the typical size of the radius of an atom? 10–2 m A 10–5 m B 10–10 m C 10–20 m D Your answer [1]
June 2018, Paper 1 Foundation, Q10 (1 mark): The electronic structure of an atom of an element is 2.8.8.2. In which period of the Periodic Table is this element found? A 1 B 2 C 4 D 8 Your answer [1]
June 2018, Paper 1 Foundation, Q11 (1 mark): The electronic structure of an atom of an element is 2.8.8.2. In which group of the Periodic Table is this element found? A 1 B 2 C 4 D 8 Your answer [1]
June 2018, Paper 1 Foundation, Q22(a) (1 mark): Which particles are present in the charge cloud? [1]
June 2018, Paper 1 Foundation, Q22(b) (1 mark): Which two particles make up the nucleus? and [1]
June 2018, Paper 1 Foundation, Q22(c) (2 marks): Most of the mass of an atom is in the nucleus. Explain why. [2]
June 2018, Paper 1 Foundation, Q22(d) (2 marks): Look at these two atoms of chlorine. 35 37 17Cl 17Cl What is the relationship between these two atoms of chlorine? Explain your answer. [2]
June 2018, Paper 3 Higher, Q13 (1 mark): Niels Bohr was involved in the development of the atomic model. Which of these statements describes his work? A He developed the idea of a nuclear atom. B He de
June 2018, Paper 3 Higher, Q19(a) (1 mark): What is meant by atomic number? [1]
June 2018, Paper 3 Higher, Q19(b) (1 mark): These two atoms of chlorine are isotopes. Explain why these two atoms of chlorine are isotopes. [1]
June 2018, Paper 3 Higher, Q19(c) (4 marks): Look at the information about other atoms and ions. Atomic Mass Number of Number of Number of Electronic Atom or ion number number protons neutrons electrons st

Questions, mark schemes and examiner’s reports are © OCR, from their published past papers. Plumi isn’t affiliated with any exam board. Want whole papers? Every OCR GCSE Chemistry A paper.

Rather write your answers by hand on iPad? Plumi marks them against the same mark schemes.

1,684 questions