The table shows the numbers of protons, neutrons and electrons in four particles, A, B, C and D.
| Particle | Number of protons | Number of neutrons | Number of electrons |
|---|---|---|---|
| A | 12 | 12 | 12 |
| B | 12 | 14 | 12 |
| C | 9 | 10 | 10 |
| D | 11 | 12 | 11 |
What is the mass number of particle D?
One of the particles in the table is an ion.
Give the letter of this particle and the charge on it.
Which two particles are isotopes of the same element?
Give a reason for your answer.
An atom of A has a relative mass of 24.0 and an atom of B has a relative mass of 26.0.
By what percentage is the relative mass of B greater than the relative mass of A?
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.