Explain why it is impossible to predict when an individual unstable nucleus will decay.

Within Half-lives and the random nature of radioactive decay, this learning objective asks you to explain why it is impossible to predict when an individual unstable nucleus will decay. Focus on the approved ideas individual, unstable, impossible, predict, when and connect them clearly to Atoms and nuclear radiation. A strong response should state the relevant particle, radiation, isotope, decay, half-life or nuclear-equation idea, then explain how it answers the exact command word. Avoid swapping nearby concepts such as atomic number and mass number, isotope and ion, alpha, beta and gamma radiation, or contamination and irradiation.