Arun
Last Activity: 6 Years ago
That depends if its molecular (chemical element fusion) or nuclear fusion, though I Think you mean the lader. Nuclear fusion is an endothermic reaction for two reasons. First, nuclei are almost Always positively charged so they repel each other, so the Only way for Them to come close is to make Them collide at very high velosities. You do this by heating Them to enormously high temperatures. And second, when nuclei repel it means that photons are travelling between Them and hit each other (roughly explained), so you can also 'push' the nuclei with photons from outside to make them come closer. And heat is photons, so if you heat it to very high temperatures both of these explanations Will fuse the atoms. This is why fusion is endothermic. Because it consumes so Much heat. The reason why you thought it was an exothermic reaction I think, is because when the two isotopes of hydrogen tritium and deuterium are fused, the biproduct is and extremely energetic neutron that will pass through everyting and radiate a lot of heat.
