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Element 46 - Palladium (Pd)
After the asteroid Pallas; discovered 1803. Free from tarnish and corrosion resistant, palladium is incorporated in contacts for telephone relays and high-grade surgical instruments. It is also used with gold, silver, and other metals as a "stiffener" in dental inlays and bridgework.
Properties
Atomic Number
:
46
Atomic Weight
:
106.42
Electron Configuration
(at ground state):
1s
2
2s
2
2p
6
3s
2
3p
6
3d
10
4s
2
4p
6
4d
10
Oxidation States
(Bold most stable):
+2
, +4
Boiling Point
(K):
3240
Melting Point (K):
1825
Density
(at 300K -- g/cm
3
):
12.0
Atomic Volume (at 300K -- cm
3
/mol)
8.90
Number of stable
isotopes
:
6
Mass Number
(Bold naturally occurring) --
Half-Life
--
Disintigration Type
:
103 -- 17.0 days -- orbital
electron capture
107 -- 7 x 10
6
years --
beta particle
(
electron
) emission
Covalent Radius (Å):
1.28
Atomic Radius (Å):
1.37
First
Ionization Potential
(V):
8.34
Electronegativity
(Pauling's):
2.20
Specific Heat
Capacity (at 300K -- J g
-1
K
-1
):
0.244
Heat of Vaporization (kJ/mol):
393.3
Heat of Fusion (kJ/mol):
16.74
Electrical Conductivity (at 293K for polycrystalline material -- 10
6
-1
cm
-1
):
10.0
Thermal Conductivity (at 300K -- W m
-1
K
-1
):
71.8
Crystal Structure:
Cubic, face centered
Acid
-
Base
Properties:
Very basic