Name the three isotopes of the element whose atomic number is 1. (b) What collective name do we give to a mixture of these three isotopes when they are present in the same ratios as in the universe as a whole?
Protium: this one has no neutrons in the nucleus
Deuterium: this one has one neutron in the nucleus ...
Isotopes of hydrogen, with atomic number of 1, is determined. There are three possible isotopes with different numbers of neutrons in the atomic shell.