Physics 9702 · AS & A Level · Atoms, nuclei and radiation
Atoms, nuclei and radiation — practice question
A uranium-235 nucleus undergoes a nuclear reaction after it absorbs a neutron. This process can be written as the equation $^{235}_{92}\text{U} + ^{W}_{X}\text{n} \rightarrow ^{93}_{37}\text{Rb} + ^{141}_{Z}\text{Cs} + Y\,^{W}_{X}\text{n}$.
(a)[3]
State the number corresponding to $W$. State the number corresponding to $X$. State the number corresponding to $Y$. State the number corresponding to $Z$.
(b)[2]
The total mass on the left side of the equation in (a) is different from the total mass on the right side. Explain why the mass appears not to be conserved.
Worked solution & mark scheme
This 5-mark question has a full step-by-step worked solution and mark scheme. One marking point: “Hence, $W = 1$ and $X = 0$.” …