Later experiments showed that the positive charge of any nucleus could be divided into a whole number of equal parts. What did scientists conclude from this?
The nucleus contains neutral particles that all have the same mass.
The nucleus contains electrons that each carry one unit of charge.
The nucleus contains a whole number of particles of equal positive charge.
The nucleus contains equal numbers of positive and negative particles.
40 exam-style questions on AQA GCSE Physics 4.1 Atoms and isotopes, covering 4.1.1 The structure of an atom, 4.1.2 Mass number, atomic number and isotopes, and 4.1.3 The development of the model of the atom (common content with chemistry). Each one has a worked solution and a mark scheme showing where the marks go.