Two different nuclides are isotopes of the same chemical element. Which statement about these two nuclides must be correct?
They have different numbers of protons.
They have different numbers of neutrons.
They have different numbers of electrons as neutral atoms.
They have different chemical properties.
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.