(a(i))[2]
Determine the numbers of protons, neutrons and electrons in a neutral tritium atom.
(a(ii))[2]
Draw a labelled diagram to show a simple model of the arrangement of the protons, neutrons and electrons in a tritium atom.
(b(i))[2]
Tritium is radioactive and changes by $\beta^{-}$ decay into an isotope of helium (He). No gamma radiation is emitted in this decay. Complete the equation for the radioactive decay of tritium: $^{3}_{1}\text{H} \rightarrow \, ^{\phantom{0}}_{\phantom{0}}\text{He} + \, ^{\phantom{0}}_{\phantom{0}}\beta + \, ^{0}_{0}X$.
(b(ii))[1]
State what particle $X$ is called.
(c)[2]
Determine the quark composition in a tritium nucleus.