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Barium
SEE PERIODIC TABLE
SEE FULL ARTICLE
Atomic Number
56
Atomic
Symbol
Ba
Atomic Weight
137.327 amu
Group
Alkaline Earth, 2
Form
Solid
Density
@
STP
3.62 g/cm
3
Melting Point
727 °C (1340.6 °F, 1000.15 °K)
Boiling Point
1897 °C (3446.6 °F, 2170.15 °K)
Heat of Fusion
7.12 kJ/mol
Heat of Vaporization
140 kJ/mol
First
Ionization Potential
5.21170 eV
Electronegativity
(on
Pauling scale
0.89
Specific Heat
Capacity
0.204 J/g K
Ground State
Electron Configuration
5p
6
6s
2
Oxidation State(s)
+2
Stable Isotopes
and
Natural Abundance
on Earth
130
Ba, 0.106%;
132
Ba, 0.101%;
134
Ba, 2.417%;
135
Ba, 6.592%;
136
Ba, 7.854%;
137
Ba, 11.23%;
138
Ba, 71.70%
Selected
Radioisotopes
133
Ba,
140
Ba
Atomic Radius
253 pm
Crystal Structure
Cubic
Discovered by
Davy, 1808