The atomic number of beryllium is 4. The mass number of a beryllium atom is 9.
Which row in the table shows the number of protons, neutrons, and electrons in a neutral atom of beryllium-9?
| Row | Protons | Neutrons | Electrons |
|---|---|---|---|
| A | 4 | 4 | 5 |
| B | 4 | 5 | 4 |
| C | 5 | 4 | 9 |
| D | 9 | 5 | 4 |
Row A
Row B
Row C
Row D
87 exam-style questions on Edexcel GCSE Chemistry 2.1 Atomic structure, covering 2.1.1 Development of the atomic model, 2.1.2 Structure of the atom and subatomic particles, 2.1.3 Mass number, isotopes and relative atomic mass, and 2.1.4 Calculating relative atomic mass from isotopic abundance. Each one has a worked solution and a mark scheme showing where the marks go.