State, using nuclide notation, the symbol for:
(i) a cobalt (atomic symbol Co\text{Co}Co) nucleus which has nucleon number 60 and proton number 27,
(ii) a gold (atomic symbol Au\text{Au}Au) nucleus which contains 79 protons and 118 neutrons.
(i) A nucleus of polonium-210 (84210Po^{210}_{84}\text{Po}84210Po) decays to a lead (atomic symbol Pb\text{Pb}Pb) nucleus by the emission of an α\alphaα-particle. Write down the nuclear equation that represents this radioactive decay.
(ii) The half-life of polonium-210 is 138 days. A sample contains 6.4×10116.4 \times 10^{11}6.4×1011 atoms of polonium-210. Predict the number of polonium-210 atoms in the sample that decay in 414 days.
484 exam-style questions on CIE IGCSE Physics 5.2 Radioactivity, covering 5.2.1 Background radiation and measuring count rate, 5.2.2a Alpha, beta and gamma emission, 5.2.2b Deflection and ionising effects of nuclear radiation, 5.2.3a Radioactive decay, 5.2.3b Effects of decay on the nucleus and decay equations, 5.2.4a Half-life, 5.2.4b Choosing isotopes for applications, and 5.2.5 Effects of ionising radiation and safety precautions. Each one has a worked solution and a mark scheme showing where the marks go.