Chlorine has two common isotopes, chlorine-35 and chlorine-37.
The atomic number of chlorine is 17.
The table shows information about some particles of chlorine.
| Particle | Atomic number | Mass number | Number of protons | Number of neutrons | Number of electrons |
|---|---|---|---|---|---|
| chlorine-35 atom | 17 | 35 | 17 | ? | 17 |
| chlorine-37 atom | 17 | 37 | ? | 20 | ? |
| chloride ion, ³⁵Cl⁻ | 17 | 35 | 17 | 18 | ? |
Complete the table.
Use the table to explain why chlorine-35 and chlorine-37 are isotopes of the same element.
Explain why the chloride ion has a negative charge.
A magnesium atom has 12 protons.
How many electrons are in a magnesium ion, Mg2+\mathrm{Mg^{2+}}Mg2+?
51 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.