|Hydrogen-1||1||1 - 1 = 0||1|
|Hydrogen-2||1||2 - 1 = 1||1|
|Hydrogen-3||1||3 - 1 = 2||1|
An isotope is named after the element and the mass number of its atoms. For example, carbon-12 is an isotope of carbon with a mass number of 12.
All three isotopes of hydrogen have identical chemical properties. This is because the number of electrons determines chemical properties, and all three isotopes have one electron in their atoms.
Relative atomic masses are given in the periodic table. They have the symbol Ar.
Take care not to confuse mass numbers and relative atomic masses:
For example, the relative atomic mass of chlorine is 35.5 rather than a whole number. This is because chlorine contains two different isotopes, chlorine-35 and chlorine-37.