Vlastnosti

CAS Number7440-39-3
PubChem CID5355457
Atomový poloměr222
Molární objem39,24
Atomová hmotnost137,327
Bloks
Teplota varu1 897
Bulk Modulus
KategorieKovy alkalických zemin
Krystalografická soustavaKubická prostorově centrovaná
BarvaStříbrná
Kovalentní poloměr215
Hustota3,594
Electrical Resistivity
Elektronová konfigurace[Xe] 6s2
Elektronů v obalu2, 8, 18, 18, 8, 2
Elektronegativita0,89
Electrons56
Skupina2
Skupenské teplo tání8
Skupenské teplo varu140
Ionizační potenciál5,212
Magnetic Ordering
Magnetic Susceptibility
Hmotnost137,327
Mass Number56
Teplota tání727
NázevBaryum
Neutrony81
Atomové číslo137
Oxidační čísla2
Perioda6
SkupenstvíPevná
Poisson Ratio
Protony56
Shear Modulus
Měrná tepelná kapacita0,204
ZnačkaBa
Tepelná vodivost0,184
Van der Waals radius
Young's Modulus
Hojnost
Hojnost v zemské kůře0.034%
Hojnost ve vesmíru1×10-6%
Ba Baryum 56 137.327 2 6 s 56 725.0 1640.0 [Xe] 6s2 2 8 18 18 8 2 3.5 0.034% Silver Cubic: Body centered 0.9 0.881 {"1":"502.9","2":"965.2","3":"3600"} 508 13.95 198 2 2.22 39.0 8.01 140.2 0.204 18.4 0 Solid, Paramagnetic, Conductor, AlkalineEarthMetal, Metal, Stable, Natural BAR-i-em Soft, slightly malleable, silvery-white metal. Barite, or barium sulfate (BaSO4), when ground is used as a filter for rubber, plastics, and resins. It is insoluable in water and so is used in X-rays of the digestive system. Barium nitrate, Ba(NO3)2, burns brilliant green and is used in fireworks. Found in barytine (BaSO4) and witherite (BaCO3), never found in pure form due to its reactivity. Must be stored under kerosene to remain pure. IQ2u1JunzgA Barium
Element 43 was predicted on the basis of the periodic table, and was erroneously reported as having been discovered in 1925, at which time it was named masurium.

The element was actually discovered by Carlo Perrier and Emilio Segrè in 1937.

It was also found in a sample of molybdenum sent by Ernest Lawrence that was bombarded by deuterons in the Berkeley cyclotron. From the Greek word technetos, artificial 56 1808 Sir Humphrey Davy England From the Greek word "barys" meaning "heavy"

Izotopy technecia

Standard Atomic Weight

137.327(7)

Stabilní izotopy

130Ba 132Ba 134Ba 135Ba 136Ba 137Ba 138Ba

Nestabilní izotopy

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

Technecium je škodlivé díky své radioaktivitě
Technetium was the first element to be produced artificially
Technetium is used in nuclear medicine to carry out a number of medical tests, mainly relating to imaging and functional studies of internal bodily organs like bone scan.

It is also used industrially for equipment calibration following its approval as a standard beta emitter.

Mild carbon steels may be effectively protected by minute quantities of technetium, but this corrosion protection is limited to closed systems because of technetium's radioactivity.