In the nuclear equation $_{11}Na^{23} + _{1}H^{1} \to _{12}Mg^{23} + x$,what does $x$ represent?

In the following nuclear reactions $_7N^{14} + _2He^4 \to _8O^{17} + X_1$ and $_{13}Al^{27} + _1D^2 \to _{14}Si^{28} + X_2$,$X_1$ and $X_2$ are respectively:

The isotope $_{92}U^{235}$ decays in a number of steps to an isotope of lead $_{82}Pb^{207}$. The groups of particles emitted in this process will be

$A$ photon of hard gamma radiation knocks a proton out of a $_{12}^{24}Mg$ nucleus to form:

The radioactive isotope $_{27}^{60}Co$,which is used in the treatment of cancer,can be produced by an $(n, p)$ reaction. For this reaction,the target nucleus is:

An artificial radioactive isotope gave $_7^{14}N$ after two successive $\beta$-particle emissions. The number of neutrons in the parent nucleus must be