Question

Does the mass of an isotope directly relate to the molar mass of the atom?

Answer 1

No, we need a multiplier, and the multiplier is Avogadro's number, `N_A`.

Explanation:

We often cite atomic mass as `12.00*g,` `""^12C`, `16.00*g`, `""^16O`, of course, here we refer to the mass of a mole, `"Avogadro's number"`, of such isotopes. Now, the actual mass of a single isotope, a single atom, is (of course) considerably less than these gram quantities. Nevertheless, chemists deal (typically) in gram quantities, and using `"Avogadro's number"` we can relate the macro world of grams and kilograms to the micro world of atoms and molecules.

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