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Element 13 - Aluminum (Al)
From
alumen
, or alum; discovered 1827. The most abundant metal, its uses range from toothpaste tubes to airplane wings. Aluminum has largely replaced coppy in cookware because, although less attractive, it is cheaper, lighter, and does not decompose vitamins during cooking.
Properties
Atomic Number
:
13
Atomic Weight
:
26.98154
Electron Configuration
(at ground state):
1s
2
2s
2
2p
6
3s
2
3p
1
Oxidation States
(Bold most stable):
+3
Boiling Point
(K):
2740
Melting Point (K):
933.5
Density
(at 300K -- g/cm
3
):
2.70
Atomic Volume (at 300K -- cm
3
/mol)
10.0
Number of stable
isotopes
:
1
Mass Number
(Bold naturally occurring) --
Half-Life
--
Disintigration Type
:
26 -- 7.2 x 10
5
years --
positron
emission, orbital
electron capture
Covalent Radius (Å):
1.18
Atomic Radius (Å):
1.43
First
Ionization Potential
(V):
5.986
Electronegativity
(Pauling's):
1.61
Specific Heat
Capacity (at 300K -- J g
-1
K
-1
):
0.90
Heat of Vaporization (kJ/mol):
290.8
Heat of Fusion (kJ/mol):
10.7
Electrical Conductivity (at 293K for polycrystalline material -- 10
6
-1
cm
-1
):
37.7
Thermal Conductivity (at 300K -- W m
-1
K
-1
):
237
Crystal Structure:
Cubic, face centered
Acid
-
Base
Properties:
Amphoteric