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Element 40 - Zirconium (Zr)
From zircon, the name of the semiprecious gem stone in which it was discovered in 1789. A metal unaffected by neutrons, zirconium serves as the inner lining of reactors in nuclear submarines and atomic power plants. It is also used as a building material for jets and rockets.
Properties
Atomic Number
:
40
Atomic Weight
:
91.224
Electron Configuration
(at ground state):
1s
2
2s
2
2p
6
3s
2
3p
6
3d
10
4s
2
4p
6
4d
2
5s
2
Oxidation States
(Bold most stable):
+4
Boiling Point
(K):
4682
Melting Point (K):
2128
Density
(at 300K -- g/cm
3
):
6.51
Atomic Volume (at 300K -- cm
3
/mol)
14.10
Number of stable
isotopes
:
5
Mass Number
(Bold naturally occurring) --
Half-Life
--
Disintigration Type
:
93 -- 1.5 x 10
4
years --
beta particle
(
electron
) emission
95 -- 64 days --
beta particle
(
electron
) emission
Covalent Radius (Å):
1.45
Atomic Radius (Å):
1.60
First
Ionization Potential
(V):
6.84
Electronegativity
(Pauling's):
1.33
Specific Heat
Capacity (at 300K -- J g
-1
K
-1
):
0.278
Heat of Vaporization (kJ/mol):
590.5
Heat of Fusion (kJ/mol):
21
Electrical Conductivity (at 293K for polycrystalline material -- 10
6
-1
cm
-1
):
2.3
Thermal Conductivity (at 300K -- W m
-1
K
-1
):
22.7
Crystal Structure:
Hexagonal
Acid
-
Base
Properties:
Amphoteric