An unstable isotope of strontium has a half-life of 28.8 years. It is a beta-minus (β−\beta^-β−) emitter and can be represented by this symbol:
3890Sr ^{90}_{38}\text{Sr} 3890SrDetermine the neutron number of this isotope.
Explain the meaning of the term half-life.
If a person ingests food or water contaminated with strontium-90, it is absorbed and incorporated into the calcium-rich structure of bones and teeth. Explain why strontium-90 inside bone tissue is a serious, long-term health hazard.
When a strontium-90 nucleus emits a β−\beta^-β−. particle, it decays to form yttrium-90 (Y\text{Y}Y). Fill in the missing numbers aaa, bbb, ccc, and ddd to complete the nuclear decay equation:
3890Sr→ baY+ dcβ− ^{90}_{38}\text{Sr} \rightarrow \> ^{a}_{b}\text{Y} + \> ^{c}_{d}\beta^- 3890Sr→baY+dcβ−Explain why strontium-90 and yttrium-90 can both be described as isotopes, even though they belong to different chemical elements with different proton numbers.
