Hi, this is my second year studying physics and few weeks ago we went in to nuclear physics very briefly because we are learning it next year. I'm not sure if the energy required to fission is equal to the energy required to fusion. For example is energy required to fission hydrogen atom, equal to fusion particles together to create hydrogen atom? (If fissioning result particles were same with fusioning particles) According to my friend who studies chemistry says it's not equal. (I do not study chemistry). Just according to E=mc2 if result of fission particles and particles required to fusion were the same, this means that mass and number of particles needed to fuse would be equal. I know that fusion is much harder to do, and we can't just put particles together to form an atom... Please give me a understandable answer.