The newest 7 of 6 written questions. Open one to see it on the real paper.
Determine the number of neutrons in this oxygen atom. Number NEUtrONS
See it on the paper →Determine the number of neutrons in the nucleus of this atom.
See it on the paper →Deduce the number of neutrons in this atom. number of neutrons =
See it on the paper →Deduce the number of neutrons in this atom of zinc. number of neutrons =
See it on the paper →Determine the difference in the number of neutrons between an atom of iron-54 and an atom of iron-56.
See it on the paper →State why this atom of magnesium has a proton number (atomic number) of 12 and a nucleon number (mass number) of 24. proton number of 12 because nucleon number of 24 because
See it on the paper →The chemical symbols of an atom of beryllium and an atom of boron are shown in Fig. 2.2. nucleon number 9 proton number 4 11 B Be 5 Fig. 2.2 Complete Table 2.1 to show the numbers of neutrons and electrons in these atoms. Table 2.1 neutrons electrons Be B
See it on the paper →The majority of candidates gave the correct answer. Some incorrectly used 29 or 64.
— Examiner report, May/June 2025, 0654/32 Q7(a)(ii) (Cambridge)
Many candidates did not give the most obvious correct answer to the first part and omitted to state that the proton number was 12 because a magnesium atom has 12 protons. The second part of the question was more successful with most candidates stating that the neutron number of 24 was due to the presence of 12 protons plus 12 neutrons.
— Examiner report, February/March 2021, 0654/42 Q2(b)(i) (Cambridge)
Many candidates gained full credit. A common error was to give boron 11 electrons.
— Examiner report, October/November 2019, 0654/33 Q2(b) (Cambridge)
Past papers, syllabus and examiner reports © UCLES (Cambridge University Press & Assessment). Questions are matched to topics from the official syllabus. AssessPro is independent and not endorsed by Cambridge.