There isn't really a specific number of isotopes that elements have to have. But the isotopes are determined by the average mass of the element found in nature. And elements have varying masses because neutrons) leave and enter the atom. (neutrons are big enough that leaving the atom cause a difference in mass but electrons leaving will not, since they are so small)
If you’re referring to H vs H2,
H is usually found in ion form as H+
H2 is the designation for pure hydrogen gas, as it is diatomic and can only exist on its own in nature if it’s bonded to another H atom.
In this case, H is an ion and H2 is hydrogen gas
The way you wrote them out, though, indicates that they could be something different. Maybe isotopes? In this case the 1 and 2 are indicative of the amount of neutrons that the atom has.
It doesn't because pepper does not dissolve
