Yes, breaking up He-4 is very endothermic. There is a triple alpha process, which was too slow to proceed much in the big bang, which converts 3 He-4 → C-12 and is exothermic.
Yes, breaking up He-4 is very endothermic. There is a triple alpha process, which was too slow to proceed much in the big bang, which converts 3 He-4 → C-12 and is exothermic.