There are three known forms of hydrogen. these forms are called (ions/copies/isotopes) of each other. each of these forms will have the same number of (neutrons/electrons/protons) but different numbers of (protons/neutrons/electrons) in their nuclei.

There are three known forms of hydrogen. These forms are called isotopes of each other. Each of these forms will have the same number of protons but different numbers of neutrons in their nuclei.

Explanation:

Conceptually, isotopes are atoms that have the same number of protons, that is, they are distinct species of the same element, differing only in the number of masses and neutrons.

Isotopes generally have the same chemical properties, as this type of property only depends on the atomic number, as is the case with solubility. However, they may have different physical properties because their masses are different, as is the case with density.

For this reason we can say that there are three known forms of hydrogen. These forms are called isotopes of each other. Each of these forms will have the same number of protons, but different numbers of neutrons in their nuclei.