By maximizing  with respect to Z, one would find the best neutron–proton ratio N/Z for a given atomic weight A. We get
This is roughly 1 for light nuclei, but for heavy nuclei the ratio grows in good agreement with experiment.
By substituting the above value of Z back into , one obtains the binding energy as a function of the atomic weight, .
Maximizing  with respect to A gives the nucleus which is most strongly bound, i.e. most stable. The value we get is A = 63 (copper), close to the measured values of A = 62 (nickel) and A = 58 (iron).
The liquid-drop model also allows the computation of fission barriers for nuclei, which determine the stability of a nucleus against spontaneous fission. It was originally speculated that elements beyond atomic number 104 could not exist, as they would undergo fission with very short half-lives, though this formula did not consider stabilizing effects of closed nuclear shells. A modified formula considering shell effects reproduces known data and the predicted island of stability (in which fission barriers and half-lives are expected to increase, reaching a maximum at the shell closures), though also suggests a possible limit to existence of superheavy nuclei beyond Z = 120 and N = 184.