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Element 12 - Magnesium (Mg)
From Magnesia, an ancient city in Asia Minor; discovered 1775; eigth most abundant element; burns as a powder or foil in firecrackers, bombs, and flash bulbs. It has one odd biological effect: a deficiency in man can have the same effect as alcoholism--delirium termens.
Properties
Atomic Number
:
12
Atomic Weight
:
24.305
Electron Configuration
(at ground state):
1s
2
2s
2
2p
6
3s
2
Oxidation States
(Bold most stable):
+2
Boiling Point
(K):
1380
Melting Point (K):
922
Density
(at 300K -- g/cm
3
):
1.74
Atomic Volume (at 300K -- cm
3
/mol)
14.0
Number of stable
isotopes
:
3
Mass Number
(Bold naturally occurring) --
Half-Life
--
Disintigration Type
:
28 -- 20.9 hours --
beta particle
(
electron
) emission
Covalent Radius (Å):
1.36
Atomic Radius (Å):
1.60
First
Ionization Potential
(V):
9.322
Electronegativity
(Pauling's):
1.31
Specific Heat
Capacity (at 300K -- J g
-1
K
-1
):
1.02
Heat of Vaporization (kJ/mol):
127.6
Heat of Fusion (kJ/mol):
8.95
Electrical Conductivity (at 293K for polycrystalline material -- 10
6
-1
cm
-1
):
22.4
Thermal Conductivity (at 300K -- W m
-1
K
-1
):
156
Crystal Structure:
Hexagonal
Acid
-
Base
Properties:
Very basic