Question
An atom of magnesium is represented as ²⁴₁₂Mg. State the number of protons and the number of neutrons in this atom.
Mark scheme (2):
- Protons = 12 (1)
- Neutrons = 12 (mass number − atomic number = 24 − 12) (1)
2 marks · take your time before peeking.
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Generated by TopMyGrade AI · cross-check official sources before relying on the mark-scheme phrasing.