How is chemical energy different from nuclear energy?

Answer 1

Chemical energy is only the result of changes in the electron orbits around nuclei.

In nuclear energy, changes to atomic nuclei occur.

In nuclear energy, nuclei are either fissioned (U235 or Pu239), or fused (deuterium + tritium), so that new elements are formed in the process. In chemical changes elements combine or dissociate, but the same elements remain after the changes.

It is actually wrong

Answer 2

Nuclear energy is derived from changes in the nucleus of the elements concerned (for example Uranium), whilst chemical energy is derived by reactions between molecules or atoms, in which the nucleus of the elements involved is not changed. For example burning methane CH4 with oxygen O2, the results are carbon dioxide CO2 and water H2O, but the amounts of each element involved, carbon, hydrogen, and oxygen remain exactly the same before and after. In the case of nuclear energy, the Uranium-235 involved is completely dismantled in the fission and two other elements are formed in its place.