101
Mendelevium
Atomic Number101
Atomic Mass258 u
CategoryActinide
State at Room TempSolid
Year Discovered1955
About Mendelevium
Named after Dmitri Mendeleev, creator of the periodic table, which predicted elements decades before they were found. The first element discovered one atom at a time: the original experiment produced just 17 atoms from a target bombarded by a trillion alpha particles. Made in tiny quantities for research on the heaviest chemistry.
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