4 Hydrogen has three naturally occurring isotopes. H.1, H-2, and H-3 The atomie mass of Hydrogen is 1.097 Which isotope is most abundant in nature? Explain​

The number following the name of the element is the number of subatomic particles inside the nucleus of the atom. This means that it is the mass number of the isotope. The average atomic mass of the element is the sum of the products of the percentage abundance and mass number of the naturally occurring isotopes.

Since, the average atomic mass of the hydrogen is nearest to 1 then, the most abundant isotope should be hydrogen-1.