A nuclide of thorium-232 is represented by 90232Th^{232}_{90}\text{Th}90232Th.
How many protons and how many neutrons are in a nucleus of this nuclide?
90 protons, 142 neutrons
90 protons, 232 neutrons
232 protons, 90 neutrons
232 protons, 142 neutrons
170 exam-style questions on CIE IGCSE Physics 5.1.2a Composition of the nucleus and isotopes. Each one has a worked solution and a mark scheme showing where the marks go.