Question

The energy level model of the nucleus describes nucleons residing in levels analogous to the energy level structure for electrons in atoms. Nuclear stability is then attributed to filled nucleon energy levels. The numbers of nucleons that result in this stability are called ______ numbers.

Answer 1

The numbers of nucleons that lead to nuclear stability are called magic numbers, much like filled electron shells in atoms lead to stability in noble gases.

Step-by-step explanation:

The numbers of nucleons that result in nuclear stability are called magic numbers. In the energy level model of the nucleus, these magic numbers correspond to full nucleon levels and include 2, 8, 20, 28, 50, 82, and 126 for either protons or neutrons.

These nucleon numbers are akin to the full electron shells in atoms that provide stability for noble gases. The band of stability defines the range of proton to neutron ratios where isotopes are stable. On this graph, isotopes with a 1:1 ratio are stable at lower atomic numbers, while heavier elements require a higher number of neutrons relative to protons due to increased proton-proton electrostatic repulsion.