A nucleus of uranium-238 (92238U^{238}_{92}\text{U}92238U) decays through a series of alpha (α\alphaα) and beta-minus (β−\beta^-β−) emissions to form a stable nucleus of radium-226 (88226Ra^{226}_{88}\text{Ra}88226Ra).
Which sequence of decays could achieve this transition?
α+α+α+β−\alpha + \alpha + \alpha + \beta^-α+α+α+β−
α+α+α+β−+β−\alpha + \alpha + \alpha + \beta^- + \beta^-α+α+α+β−+β−
α+α+β−+β−\alpha + \alpha + \beta^- + \beta^-α+α+β−+β−
α+α+α+α+β−+β−\alpha + \alpha + \alpha + \alpha + \beta^- + \beta^-α+α+α+α+β−+β−
128 exam-style questions on AQA A Level Physics Radioactivity (A-level only), covering Rutherford scattering (A-level only), $\alpha$ , $\beta$ and $\gamma$ radiation (A-level only), Radioactive decay (A-level only), Nuclear instability (A-level only), Nuclear radius (A-level only), Mass and energy (A-level only), Induced fission (A-level only), and Safety aspects (A-level only). Each one has a worked solution and a mark scheme showing where the marks go.