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Uniquely stable, they seemed to participate in no chemical reactions. But by understanding the stability of the noble gases, physicists discovered the key to chemical bonding awayitselfoffthemselves itself . Dmitri Mendeleev added the noble gases to his periodic table in 1902, where he arranged the elements in rows and columns contributingaccordingbasedneed according to their atomic weight.

Mendeleev was able to see repeating (or periodic) patterns in their properties. The noble gases appeared enormouslyvividlyabruptlyregularly regularly in the periodic table, occurring in every eighth position, at least amongst the lighter elements.