>>13511667fire released is evidence of undergoing a chemical change, not a nuclear one. in fact, if you weighed the output of the chemical equation (the ashes, the gases released) the weight as well as the number of molecules would balance.
you can bring the original substance back in this case easily. spread the ashes in with fertile soil. CO2 and H20 are both gaseous product and a plant will also take advantage of both of those.
Further, you can "uncrack" an egg the same way, by mixing in the egg in with some chicken food and feeding it to a chicken, though your yield won't be nearly good enough to have this as a viable long term option.
your mistake was that you assumed fire destroyed mass. it doesn't. law of conservation exists for both mass and energy. some energy is created (and coinciding with that situation; mass is destroyed) in nuclear reactions.
