Lanthan
57
La
Skupina
n/a
Perioda
6
Blok
f
Protony
Elektrony
Neutrony
57
57
82
Hlavní vlastnosti
Atomové číslo
57
Atomová hmotnost
138,90547
Hmotnostní číslo
139
Kategorie
Lanthanoidy
Barva
Stříbrná
Radioaktivní
Ne
From the Greek word lanthanein, to lie hidden
Krystalografická soustava
Hexagonální
Historie
Lanthanum was discovered in 1839 by Swedish chemist Carl Gustav Mosander.
He partially decomposed a sample of cerium nitrate by heating and treating the resulting salt with dilute nitric acid.
From the resulting solution, he obtained a pale brick colored oxide of the new rare earth.
Lanthanum was isolated in relatively pure form in 1923.
He partially decomposed a sample of cerium nitrate by heating and treating the resulting salt with dilute nitric acid.
From the resulting solution, he obtained a pale brick colored oxide of the new rare earth.
Lanthanum was isolated in relatively pure form in 1923.
Elektronů v obalu
2, 8, 18, 18, 9, 2
Elektronová konfigurace
[Xe] 5d1 6s2
Lanthanum is the most reactive of the rare earth metals
Fyzické vlastnosti
Skupenství
Pevná
Hustota
6,145 g/cm3
Teplota tání
1193,15 K | 920 °C | 1688 °F
Teplota varu
3737,15 K | 3464 °C | 6267,2 °F
Skupenské teplo tání
6,2 kJ/mol
Skupenské teplo varu
400 kJ/mol
Měrná tepelná kapacita
0,195 J/g·K
Hojnost v zemské kůře
0,0034%
Hojnost ve vesmíru
2×10-7%
Číslo CAS
7439-91-0
PubChem CID číslo
23926
Atomové vlastnosti
Atomový poloměr
187 pm
Kovalentní poloměr
207 pm
Elektronegativita
1,1 (Paulingova stupnice)
Ionizační potenciál
5,5769 eV
Molární objem
22,5 cm3/mol
Tepelná vodivost
0,135 W/cm·K
Oxidační čísla
2, 3
Aplikace
Lanthanum is used in large quantities in batteries for hybrid automobiles.
It is also used to make night vision goggles.
Small amounts of lanthanum, as an additive, can be used to produce nodular cast iron.
Lanthanum carbonate is used to reduce blood levels of phosphate in patients with kidney disease.
It is also used to make night vision goggles.
Small amounts of lanthanum, as an additive, can be used to produce nodular cast iron.
Lanthanum carbonate is used to reduce blood levels of phosphate in patients with kidney disease.
Lanthan a jeho sloučeniny jsou považovány za mírně toxické
Izotopy
Stabilní izotopy
139LaNestabilní izotopy
117La, 118La, 119La, 120La, 121La, 122La, 123La, 124La, 125La, 126La, 127La, 128La, 129La, 130La, 131La, 132La, 133La, 134La, 135La, 136La, 137La, 138La, 140La, 141La, 142La, 143La, 144La, 145La, 146La, 147La, 148La, 149La, 150La, 151La, 152La, 153La, 154La, 155La