State what is meant by the term isotopes in terms of subatomic particles.
Element X\text{X}X has two naturally occurring isotopes. Their mass numbers are 191191191 and 193193193.
The percentage abundance of each isotope is:
Estimate the relative atomic mass of element X\text{X}X by selecting one of the following ranges:
In 1911, Rutherford's alpha particle scattering experiment disproved the plum pudding model. Explain how two specific observations from this experiment led to the proposal of the nuclear model of the atom.
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.