Mendelevium

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General Properties
Atomic number Predicted atomic mass Half-life of longest living isotope Electron Configuration First developed
101 258amu Around 28 days [Rn] 5f13 7s2 1955
General Properties
Atomic number 101
Atomic mass 258amu
Half-life of longest living isotope Around 28 days
Electron Configuration [Rn] 5f13 7s2
First discovered 1955

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Description and uses

Mendelevium is the 101st element of the periodic table. It was developed in 1955 by a group of researchers after they bombarded einsteinium with alpha particles. Its longest living isotope is 260Md, with a half-life of around 28 days.

T&C