On the P.T.E., the atomic mass number of an element gives the number of protons and neutrons in its nucleus, ie. the number of particles in its nucleus. But this number also gives that particular elements molar mass, correct? eg. For carbon, it has 12 particles in its nucleus, and its molar mass is 12g, that is, 12g of Carbon 12 will have 6.022 times 10^23 atoms. Both of these come from its atomic mass number, 12. How does the atomic mass number give both of these?