11.1 Atoms, nuclei and radiation

1 infer from the results of the α-particle scattering experiment the existence and small size of the nucleus
2 describe a simple model for the nuclear atom to include protons, neutrons and orbital electrons
3 distinguish between nucleon number and proton number
4 understand that isotopes are forms of the same element with different numbers of neutrons in their nuclei
5 understand and use the notation A ZX for the representation of nuclides
6 understand that nucleon number and charge are conserved in nuclear processes
7 describe the composition, mass and charge of α-, β- and γ-radiations (both β– (electrons) and β+ (positrons) are included)
8 understand that an antiparticle has the same mass but opposite charge to the corresponding particle,
and that a positron is the antiparticle of an electron
9 state that (electron) antineutrinos are produced during β– decay and (electron) neutrinos are produced during β+decay
10 understand that α-particles have discrete energies but that β-particles have a continuous range of energies because (anti)neutrinos are emitted in β-decay
12 use the unified atomic mass unit (u) as a unit of mass