A nucleus of \(_{\;{\text{79}}}^{{\text{199}}}{\text{Au}}\) decays to a nucleus of \(_{\;{\text{80}}}^{{\text{199}}}{\text{Hg}}\). State the two particles, other than \(\gamma \)-photon, emitted in this decay.

electron/beta (condone lack of sign);

anti neutrino / \(\bar v\);

Allow undefined symbols if unambiguous.

Most candidates could write with confidence about the repulsive nature of the proton-proton interaction and the attractive nature of the strong nuclear force. Few gave good accounts of the balance between these two forces or described the energy situation (a better way to answer). Weak candidates could not name the strong nuclear force adequately.