Chemistry › Isotope
Mendeleev · Isotope
Hydrogen-2 (deuterium)
Hydrogen-2 (deuterium): atomic number 1, mass number 2, with 1 protons and 1 neutrons.
IsotopeH
21H
Protons1
Neutrons1
Electrons (neutral)1
The proton count fixes the element: 1 protons identify Hydrogen. Mass number 2 is the total number of protons and neutrons.
A neutral Hydrogen-2 (deuterium) atom also has 1 electrons. Changing neutrons changes the isotope; changing electrons changes the charge.