Two of the isotopes of helium are helium-3 (23He^{3}_{2}\text{He}23He) and helium-4 (24He^{4}_{2}\text{He}24He).
State one similarity in the composition of their nuclei.
Describe how a nucleus of helium-4 differs from a nucleus of helium-3.
In a star's core, a nucleus of helium-3 fuses with another nucleus of helium-3 at an extremely high temperature. This fusion reaction produces a nucleus of helium-4 and two protons.
Explain why an extremely high temperature is needed when forcing these two nuclei together.
Complete the nuclear equation for this fusion reaction using nuclide notation:
23He+23He→‾ ^{3}_{2}\text{He} + {^{3}_{2}\text{He}} \rightarrow \underline{\quad\quad\quad\quad\quad\quad} 23He+23He→170 exam-style questions on CIE IGCSE Physics 5.1.2a Composition of the nucleus and isotopes. Each one has a worked solution and a mark scheme showing where the marks go.