basic atom & molecule physics After 30 views, I hadn't received any replies to this thread as posted in the "atoms" forum. Perhaps someone here can help me out. Thanks, Glenn 1. Why exactly does a covalent bond work? I understand how the electrons fill up the shells and so forth, but why does it work. Is the bond caused by the two atoms "competing" for the same electron that pulls them together? Is that a correct analogy? 2. Are electrons EXACTLY the same charge as the proton? 3. How is the bond angle in H2O predicted by physics? 4. What dictates how many electrons can occupy a shell?