Physics 9702 · AS & A Level · Atoms, nuclei and radiation
Atoms, nuclei and radiation — practice question
A nucleus Q that is isolated and stationary decays to nucleus R plus an $\alpha$-particle. The $\alpha$-particle has a speed of $1.5 \times 10^7\,\text{m s}^{-1}$.
(a)[1]
Complete the equation for this decay: $^{\phantom{0}}_{88}Q \rightarrow \,^{222}_{\phantom{0}}R + \,^{4}_{2}\alpha$.
(b)[3]
Using momentum conservation, Calculate the speed of nucleus R after the decay.
(c)[3]
State three quantities that remain conserved during the decay.
Worked solution & mark scheme
This 7-mark question has a full step-by-step worked solution and mark scheme. One marking point: “The nucleon number of Q is $226$ and the proton number of R is $86$” …