How many protons and how many neutrons are in a nucleus of 88226Ra^{226}_{88}\text{Ra}88226Ra?
88 protons, 138 neutrons
88 protons, 226 neutrons
138 protons, 88 neutrons
226 protons, 88 neutrons
284 exam-style questions on CIE IGCSE Physics 5.1 The nuclear model of the atom, covering 5.1.1a Structure of the atom and ions, 5.1.1b Alpha-particle scattering, 5.1.2a Composition of the nucleus and isotopes, 5.1.2b Proton number, nucleon number and nuclide notation, and 5.1.2c Nuclear fission and nuclear fusion. Each one has a worked solution and a mark scheme showing where the marks go.