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Chart of Nuclides

A Chart of Nuclides is a graph in which one axis represents the number of neutrons and the other represents the number of protons in an atomic nucleus. Points are plotted on the graph where real nuclides are known to exist. This system of ordering nuclides offers insight into the characteristics of isotopes.

In the link provided above, the vertical axis is the atomic number, which is the number of protons, also identifying the element, and the horizontal axis is the number of neutrons in the nucleus. The atomic weight of an isotope is the sum of protons and neutrons. The element name and the atomic weight identify an isotope, for example, Carbon-14, which has 6 protons and 8 neutrons.

This chart of nuclides is rather complex to navigate, but is provided for those individuals who wish to explore a little on their own.