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Element 99 - Einsteinium (Es)

After Albert Einstein; discovered 1952. It was first detected in the debris from a 1952 H-bomb explosion in the Pacific after tons of radioactive coral from atolls in the blast area were sifted and examined. The element was later made in a nuclear reactor.

Properties
Atomic Number:	99
Atomic Weight:	(252)
Electron Configuration (at ground state):	1s²2s²2p⁶3s²3p⁶3d¹⁰4s²4p⁶4d¹⁰5s²5p⁶4f¹⁴5d¹⁰5f¹¹6s²6p⁶7s²
Oxidation States (Bold most stable):	+3
Melting Point (K):	1130
Mass Number (Bold naturally occurring) -- Half-Life -- Disintigration Type:	252 -- 472 days -- alpha particle emission 253 -- 20.47 days -- alpha particle emission 254 -- 276 days -- alpha particle emission
First Ionization Potential (V):	6.42
Electronegativity (Pauling's):	1.3
Thermal Conductivity (at 300K -- W m^-1 K^-1):	10

Element 99 - Einsteinium (Es)

Properties