Massive amounts of destructive energy are released when a nuclear fission bomb exploded. where does that energy come from?

Explanation:

Nuclear fission : it a process in which large unstable nucleus splits into stable smaller stable nuclei. During this spilling large amount of energy is released.

The massive amounts of destructive energy is released during nuclear bomb explosion. The source of this energy, is the splitting of larger nucleus into smaller nuclei which releases large amount of energy.

chemical changes occur when a substance combines with another to form a new substance, called chemical synthesis or, alternatively, chemical decomposition into two or more different substances. these processes are called chemical reactions and, in general, are not reversible except by further chemical reactions. some reactions produce heat and are called exothermic reactions and others may require heat to enable the reaction to occur, which are called endothermic reactions. understanding chemical changes is a major part of the science of chemistry.