Chemistry › Isotope
Mendeleev · Isotope
Carbon-12
Carbon-12: atomic number 6, mass number 12, with 6 protons and 6 neutrons.
IsotopeC
126C
Protons6
Neutrons6
Electrons (neutral)6
The proton count fixes the element: 6 protons identify Carbon. Mass number 12 is the total number of protons and neutrons.
A neutral Carbon-12 atom also has 6 electrons. Changing neutrons changes the isotope; changing electrons changes the charge.