Describe the structure of an atom in terms of its subatomic particles, including where each type of particle is found and the relative charge of each.
Written & reviewed by James Millett — Biology (Imperial College London), PGCE Science (University of Cambridge).
Model answer (4 marks)
The nucleus is at the centre of the atom.
The nucleus contains protons and neutrons.
Electrons are found outside the nucleus, orbiting it.
Protons carry a positive charge, electrons a negative charge (neutrons are neutral).
The nucleus contains protons and neutrons.
Electrons are found outside the nucleus, orbiting it.
Protons carry a positive charge, electrons a negative charge (neutrons are neutral).
Examiner tips
- Use the exact wording from the mark scheme – e.g. "nucleus is found at the centre". Mention the charge of each particle. Keep the answer short and to the point to fit the 4‑mark limit.
- common_mistakes
- :
- Writing "electrons are in the nucleus" – they are outside. Omitting the charge of protons or electrons. Including extra information such as electron shells or energy levels.
Mark scheme (4 marks)
- The nucleus is found at the centre of the atom
- The nucleus contains protons (and neutrons)
- Electrons are found outside the nucleus / orbit the nucleus
- Protons have a positive charge and electrons have a negative charge (neutrons have no/neutral charge — award if stated)
Key terms in this question
Related
- All Eduqas GCSE Physics revision notes →
- How to answer a "Describe" question →
- Decode the mark scheme abbreviations →
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