The nuclide notation ZAX{}^A_Z XZAX describes the nucleus of a specific atom.
State what is represented by each of the following symbols:
A radioactive isotope has a half-life of 4.0 hours4.0\text{ hours}4.0 hours. A sample of this isotope has an initial mass of 56 mg56\text{ mg}56 mg. Calculate the mass of this isotope that remains in the sample after 12 hours12\text{ hours}12 hours.
The sample decays by emitting an α\alphaα-particle. Describe the nature of an α\alphaα-particle.
Describe how the nucleus of the isotope changes (in terms of proton number and nucleon number) due to the emission of an α\alphaα-particle.
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.