Chlorine naturally exists as two isotopes ... 75 atoms have a mass number of 35, and 25 atoms have a mass number of 37. To calculate the relative atomic mass, A r, of chlorine: \(\textit ...

While the number of protons defines the element (e.g., hydrogen, carbon, etc.) and the sum of the protons and neutrons gives the atomic mass, the number of neutrons defines the isotope of that element ...

This variation in the relative abundance of stable isotopes results from tiny mass differences that cause ... Deuterium (the heavy hydrogen isotope) has revolutionized stable isotope analysis ...