This question is about atoms, isotopes, and relative atomic mass.
An atom of element X has:
Determine the number of electrons and the number of neutrons in this neutral atom of element X.
Select your answers from the following options: 14, 16, 30, 44.
The table below shows the abundance of the two naturally occurring isotopes of element Y.
| Isotope | Mass number | Percentage abundance (%) |
|---|---|---|
| Isotope 1 | 79 | 50.7 |
| Isotope 2 | 81 | 49.3 |
Calculate the relative atomic mass (ArA_rAr) of element Y.
Use the data in the table and the equation:
Ar=(mass number×percentage) of isotope 1+(mass number×percentage) of isotope 2100 A_r = \frac{(\text{mass number} \times \text{percentage}) \text{ of isotope 1} + (\text{mass number} \times \text{percentage}) \text{ of isotope 2}}{100} Ar=100(mass number×percentage) of isotope 1+(mass number×percentage) of isotope 2Give your answer to 3 significant figures.
Using your answer to part (b) and a periodic table, suggest the identity of element Y.
41 exam-style questions on AQA GCSE Chemistry 1.1 A simple model of the atom, symbols, relative atomic mass, electronic charge and isotopes, covering 1.1.1 Atoms, elements and compounds, 1.1.2 Mixtures, 1.1.3 The development of the model of the atom (common content with physics), 1.1.4 Relative electrical charges of subatomic particles, 1.1.5 Size and mass of atoms, 1.1.6 Relative atomic mass, and 1.1.7 Electronic structure. Each one has a worked solution and a mark scheme showing where the marks go.