Barium

56
Ba
Gruppe
2
Periode
6
Blok
s
Protons
Electrons
Neutrons
56
56
81
General Properties
Atomnummer
56
Atommasse
137,327
Mass Number
137
Kategori
Jordalkalimetaller
Farve
Silver
Radioactive
Nej
From the Greek word barys, heavy
Krystalstruktur
Rumcentreret Kubisk
History
Barium was identified as a new element in 1774 by Carl Wilhelm Scheele.

Barium was first isolated by electrolysis of molten barium salts in 1808, by Sir Humphry Davy in England.

Robert Bunsen and Augustus Matthiessen obtained pure barium by electrolysis of a molten mixture of barium chloride and ammonium chloride.
Elektroner i hver skal
2, 8, 18, 18, 8, 2
Elektronkonfiguration
[Xe] 6s2
Ba
At low doses, barium acts as a muscle stimulant
Physical Properties
Tilstandsform
Fast stof
Massefylde
3,594 g/cm3
Smeltepunkt
1000,15 K | 727 °C | 1340,6 °F
Kogepunkt
2170,15 K | 1897 °C | 3446,6 °F
Smeltevarme
8 kJ/mol
Fordampningsvarme
140 kJ/mol
Varmefylde
0,204 J/g·K
Abundance in Earth's crust
0,034%
Abundance in Universe
1×10-6%
Barium
Billede akkrediteringer: Images-of-elements
Barium with a grey oxide layer under argon
CAS Number
7440-39-3
PubChem CID Number
5355457
Atomic Properties
Atomradius
222 pm
Kovalent radius
215 pm
Elektronegativitet
0,89 (Paulings skala)
Ionization Potential
5,2117 eV
Atomic Volume
39,24 cm3/mol
Varmeledningsevne
0,184 W/cm·K
Oxidationstrin
2
Applications
Barium is used as a flashed getter in vacuum tubes to remove the last traces of gases.

It is often used in barium-nickel alloys for spark plug wire.

Barium sulfate is important to the petroleum industry as a drilling fluid in oil and gas wells.

Barium is also used in medicine to detect abnormalities in the digestive system.
Water-soluble barium compounds are poisonous
Isotoper
Stable Isotopes
130Ba, 132Ba, 134Ba, 135Ba, 136Ba, 137Ba, 138Ba
Unstable Isotopes
114Ba, 115Ba, 116Ba, 117Ba, 118Ba, 119Ba, 120Ba, 121Ba, 122Ba, 123Ba, 124Ba, 125Ba, 126Ba, 127Ba, 128Ba, 129Ba, 131Ba, 133Ba, 139Ba, 140Ba, 141Ba, 142Ba, 143Ba, 144Ba, 145Ba, 146Ba, 147Ba, 148Ba, 149Ba, 150Ba, 151Ba, 152Ba, 153Ba