For example, carbon has three naturally occurring isotopes: all of its atoms have six protons and most have six neutrons as well, but about one per cent have seven neutrons, and a very small fraction have eight neutrons.
For eksempel har carbon tre naturligt forekommende isotoper: alle dets atomer har seks protoner, og de fleste har også seks neutroner, men omkring 1% har syv neutroner, og en meget lille andel har otte neutroner.