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Element 73 - Tantalum (Ta)
From King Tantalus of Greek myth; discovered 1802. Almost impervious to corrosion, tantalum is vital in surgical repairs of the human body; it can replace bone (for example in skull plates); as foil or wire it connects torn nerves; as woven gaurze it binds up abdominal muscles.
Properties
Atomic Number
:
73
Atomic Weight
:
180.9479
Electron Configuration
(at ground state):
1s
2
2s
2
2p
6
3s
2
3p
6
3d
10
4s
2
4p
6
4d
10
4f
14
5s
2
5p
6
5d
3
6s
2
Oxidation States
(Bold most stable):
+5
Boiling Point
(K):
5730
Melting Point (K):
3293
Density
(at 300K -- g/cm
3
):
16.65
Atomic Volume (at 300K -- cm
3
/mol)
10.90
Number of stable
isotopes
:
2
Mass Number
(Bold naturally occurring) --
Half-Life
--
Disintigration Type
:
182 -- 115.0 days --
beta particle
(
electron
) emission
Covalent Radius (Å):
1.34
Atomic Radius (Å):
1.49
First
Ionization Potential
(V):
7.89
Electronegativity
(Pauling's):
1.5
Specific Heat
Capacity (at 300K -- J g
-1
K
-1
):
0.14
Heat of Vaporization (kJ/mol):
737.0
Heat of Fusion (kJ/mol):
36
Electrical Conductivity (at 293K for polycrystalline material -- 10
6
-1
cm
-1
):
8.1
Thermal Conductivity (at 300K -- W m
-1
K
-1
):
57.5
Crystal Structure:
Cubic, body centered
Acid
-
Base
Properties:
Slightly acidic