An atom of element Z has a mass number of 52.
The nucleus of the atom contains 4 more neutrons than protons.
Z forms an ion, Z3+\mathrm{Z^{3+}}Z3+.
How many electrons are in one Z3+\mathrm{Z^{3+}}Z3+ ion?
21
24
25
27
101 exam-style questions on OCR GCSE Chemistry 1.2 Atomic structure, covering 1.2.1 Development of the atomic model, 1.2.2 The nuclear model and the size of atoms, and 1.2.3 Subatomic particles in atoms and ions. Each one has a worked solution and a mark scheme showing where the marks go.