Dietary iodine is predominantly the stable isotope iodine-127, whereas medical imaging of the thyroid often utilises the radioactive isotope iodine-131.
Compare the nuclear composition of these two isotopes. State one similarity and one difference between the particles contained within a nucleus of iodine-127 and a nucleus of iodine-131.
81 exam-style questions on Edexcel GCSE Physics 6.1 Atomic structure and isotopes, covering 6.1.1 Structure of the atom, 6.1.2 Isotopes: atomic and mass number, 6.1.3 Sub-atomic particles: masses and charges, and 6.1.4 Electron orbits and energy changes. Each one has a worked solution and a mark scheme showing where the marks go.