Chemistry › Isotope
Mendeleev · Isotope
Oxygen-16
Oxygen-16: atomic number 8, mass number 16, with 8 protons and 8 neutrons.
IsotopeO
168O
Protons8
Neutrons8
Electrons (neutral)8
The proton count fixes the element: 8 protons identify Oxygen. Mass number 16 is the total number of protons and neutrons.
A neutral Oxygen-16 atom also has 8 electrons. Changing neutrons changes the isotope; changing electrons changes the charge.