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Element 103 - Lawrencium (Lr)
After Ernest O. Lawrence. Discovered in 1961 at Lawrence Radiation Laboratories, lawrencium was made by bombardment of californium with boron in a chamber fitted with a copper conveyer; the new atoms, one at a time, were carried to a radiation detector for identification.
Properties
Atomic Number
:
103
Atomic Weight
:
(260)
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
14
6s
2
6p
6
6d
1
7s
2
Oxidation States
(Bold most stable):
+3
Melting Point (K):
1900
Mass Number
(Bold naturally occurring) --
Half-Life
--
Disintigration Type
:
260 -- 3.0 minutes --
alpha particle
emission
Electronegativity
(Pauling's):
1.3
Thermal Conductivity (at 300K -- W m
-1
K
-1
):
10