特性

CAS Number7440-39-3
PubChem CID5355457
原子半径222
モル体積39.24
原子量137.327
ブロックs
沸点1,897
Bulk Modulus
カテゴリアルカリ土類金属
結晶構造体心立方格子
銀色
共有結合半径215
密度3.594
Electrical Resistivity
電子配置[Xe] 6s2
電子殻2, 8, 18, 18, 8, 2
電気陰性度0.89
Electrons56
2
融解熱8
蒸発熱140
イオン化エネルギー5.212
Magnetic Ordering
Magnetic Susceptibility
質量137.327
Mass Number56
融点727
名称バリウム
中性子81
原子番号137
酸化数2
周期6
固体
Poisson Ratio
陽子56
Shear Modulus
熱容量0.204
記号Ba
熱伝導率0.184
Van der Waals radius
Young's Modulus
天然存在比
地殻中における存在比0.034%
宇宙空間における存在比1×10-6%
Ba バリウム 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"

テクネチウムの同位体

Standard Atomic Weight

137.327(7)

安定同位体

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

不安定同位体

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

Technetium is harmful due to its radioactivity
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.