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Element 100 - Fermium (Fm)
After Enrico Fermi; discovered 1953. Fermium, like einsteinium, was first isolated from the debris of the 1952 H-bomb test, having been produced from the fission of uranium. Because of its short life-span, scientists doubt that enough fermium will ever be obtained to be weighed.
Properties
Atomic Number
:
100
Atomic Weight
:
(257)
Electron Configuration
(at ground state):
1s
2
2s
2
2p
6
3s
2
3p
6
3d
10
4s
2
4p
6
4d
10
5s
2
5p
6
4f
14
5d
10
5f
12
6s
2
6p
6
7s
2
Oxidation States
(Bold most stable):
+3
Melting Point (K):
1800
Mass Number
(Bold naturally occurring) --
Half-Life
--
Disintigration Type
:
255 -- 20.1 hours --
alpha particle
emission
257 -- 100.5 days --
alpha particle
emission
First
Ionization Potential
(V):
6.50
Electronegativity
(Pauling's):
1.3
Thermal Conductivity (at 300K -- W m
-1
K
-1
):
10