The table shows the numbers of protons, neutrons and electrons in four particles, W, X, Y and Z.
| Particle | Protons | Neutrons | Electrons |
|---|---|---|---|
| W | 16 | 16 | 16 |
| X | 16 | 18 | 18 |
| Y | 18 | 22 | 18 |
| Z | 19 | 20 | 18 |
Which statement is correct?
W and X have the same mass number.
X and Z are ions with the same charge.
W and Y are atoms of the same element.
Z is a 1+ ion and has mass number 39.
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.