Hydrogen-1, Carbon-13, Nitrogen-15, Fluorine-19, and Phosphorus-31 are the most useful. Out of these, Hydrogen-1 and Carbon-13 in NMR are the most useful nuclei because the these atoms are the most commonly present in organic molecules.
1 the reproductive system. and the immune system is there to fight off any viruses or bacteria that had entered your body. If the bacteria is harmful it will be fought.
