Physics (AS & A Level) · Oct / Nov 2025 · Paper 13 · Question 39

The number of electrons in a neutral atom of an isotope of plutonium, $^{239}_{94}\text{Pu}$, is changed to produce a charged atom (ion) W. W has an overall charge of $+1.6 \times 10^{-19}$ C. How many protons, neutrons and electrons are in W?

1. Aprotons 94, neutrons 145, electrons 93
2. Bprotons 94, neutrons 145, electrons 95
3. Cprotons 238, neutrons 94, electrons 239
4. Dprotons 239, neutrons 94, electrons 238

As printed in the paper