I don't understand Avogadro's number when dealing with relative molecular weights. I understand that the relative atomic weights of the various elements are each equal to avogadro's number. But take for example water, H2O. If Avogadro's number is equal to the relative atomic weight of whatever element, then shouldn't the total number of atoms in H2O be avogadro's number multiplied by 3? Instead, H2O is equal to avogadro's number for some reason which I don't understand. Note: I'm not sure if these kinds of questions belong in this part of the forums. It's not a homework problem thought, so I dunno.