Hydrogen has an atomic number of 1.
This means that hydrogen atoms have a single proton. They also have a
single electron: this is lost when a hydrogen atom turns into a hydrogen
ion.
However, there are three different isotopes of
hydrogen: normal hydrogen atoms do not have any neutrons; their atomic
mass is 1. Radioactive hydrogen (tritium) also has two neutrons that
makes it three times as heavy as a normal hydrogen atom and makes it
radioactive; it has an atomic mass
of 3. Don't wait for it to decay because I have not programmed this atom
to do so yet.
