Polonium-210 (84210Po^{210}_{84}\text{Po}84210Po) is an extremely toxic radioactive isotope that decays by emitting alpha radiation.
Complete the nuclear decay equation for Polonium-210 by determining the missing mass number AAA and atomic number ZZZ for Lead (Pb\text{Pb}Pb):
84210Po→ZAPb+24He ^{210}_{84}\text{Po} \to ^{A}_{Z}\text{Pb} + ^{4}_{2}\text{He} 84210Po→ZAPb+24HePolonium-210 is highly lethal if ingested, inhaled, or absorbed into the bloodstream (internal contamination), yet external exposure to a source of Polonium-210 poses almost no danger to health. Explain this difference in risk in terms of the properties of alpha radiation.
A forensic laboratory analyses a contaminated item and detects a remaining mass of 1.25×10−6 g1.25 \times 10^{-6}\text{ g}1.25×10−6 g of Polonium-210. The contamination is known to have occurred exactly 414 days414\text{ days}414 days prior to the measurement. Given that the half-life of Polonium-210 is 138 days138\text{ days}138 days, calculate the initial mass of the Polonium-210 deposited on the item.
6 exam-style questions on AQA GCSE Physics 4.2 Atoms and nuclear radiation, covering 4.2.1 Radioactive decay and nuclear radiation, 4.2.2 Nuclear equations, 4.2.3 Half-lives and the random nature of radioactive decay, and 4.2.4 Radioactive contamination. Each one has a worked solution and a mark scheme showing where the marks go.