Physics (AS & A Level) · Feb / March 2016 · Paper 12 · Question 39

A nucleus of magnesium decays into a nucleus of sodium by emitting a β+ particle. The decay is represented by the equation shown. \[^{23}_{12}\text{Mg} \rightarrow ^{P}_{Q}\text{Na} + ^{0}_{+1}\beta\] What are the values of P and Q?

1. AP = 22, Q = 11
2. BP = 22, Q = 13
3. CP = 23, Q = 11
4. DP = 23, Q = 13

As printed in the paper