There are three known forms of hydrogen. These forms are called A. Isotopes, B. Copies, C. Ions, of each other. Each of these forms will have the same number of A. Protons, B. Neutrons, C. Electron, but different numbers of A. Protons, B. Neutrons, C. Electrons, in their nuclei.

Respuesta :

There are three known forms of hydrogen. These forms are called  Isotopes (option A) of each other. 

Each of these forms will have the same number of Protons (Option A)
 
but different numbers of  Neutrons (Option B) in their nuclei.

The diagram can help you in understanding and having a visual version to remember.

Ver imagen JoshEast