Caesium-137 (55137Cs^{137}_{55}\text{Cs}55137Cs) is an isotope of caesium.
Which of the isotopes given in Table 1 is not an isotope of caesium? Give a reason for your answer.
Table 1
| Isotope | Mass number | Atomic number |
|---|---|---|
| X | 135 | 55 |
| Y | 134 | 55 |
| Z | 134 | 54 |
How many years does it take for the number of caesium-137 nuclei to decrease from 8000 to 4000?
What is the half-life of caesium-137?
Atoms and nuclear radiation Questions
Practise AQA GCSE Physics Atoms and nuclear radiation with exam-style questions for Foundation and Higher tier. 21 questions covering Radioactive decay and nuclear radiation, Nuclear equations, Half-lives and the random nature of radioactive decay, and Radioactive contamination, matched to the AQA GCSE Physics (8463) specification and written in Paper 1 and Paper 2 style. Every question includes a full worked solution and mark scheme, so you can see where marks are awarded rather than just whether you got the answer right.