Heavy stable nuclei such as contain significantly more neutrons than protons
PHYSICS · Single correct · A Level · Physics · Nuclear physics · Nuclear physics
Problem
Heavy stable nuclei such as 208Pb contain significantly more neutrons than protons. Which of the following statements best explains this fact?
(a) Extra neutrons make the nucleus electrically neutral overall, thereby cancelling proton–proton Coulomb repulsion.
(b) Extra neutrons increase the nuclear density, causing the strong force to grow and overcome electrostatic forces.
(c) Neutrons provide additional strong nuclear attraction without adding Coulomb repulsion, helping to counterbalance the proton–proton repulsive force.
(d) Additional neutrons are heavier, so their greater mass contributes a larger mass defect and thus larger binding energy.