The table below shows the relative mass and relative charge of protons, neutrons, and electrons. Some values are missing.
| Subatomic particle | Relative mass | Relative charge |
|---|---|---|
| Proton | 1 | [ W ] |
| Neutron | [ X ] | 0 |
| Electron | [ Y ] | [ Z ] |
State the values of [ W ], [ X ], [ Y ], and [ Z ].
The chemical symbol for an atom of one isotope of magnesium is 1225Mg{}_{12}^{25}\text{Mg}1225Mg.
(i) State the number of protons, neutrons, and electrons present in one neutral atom of this isotope.
(ii) Explain what is meant by the term isotopes in terms of subatomic particles.
Bromine has two naturally-occurring isotopes with mass numbers 79 and 81. A sample of bromine contained the two isotopes in the following proportions:
Use this information to calculate the relative atomic mass of bromine. Give your answer to two decimal places.
