Lantan

57
La
Gruppe
I/T
Periode
6
Blokk
f
Protoner
Elektroner
Nøytroner
57
57
82
Generelle egenskaper
Atomnummer
57
Atomvekt
138,90547
Massetall
139
Kategori
Lantanoider
Farge
Sølv
Radioaktiv
Nei
From the Greek word lanthanein, to lie hidden
Krystallstruktur
Simple Hexagonal
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.
Elektroner per energinivå
2, 8, 18, 18, 9, 2
Elektronkonfigurasjon
[Xe] 5d1 6s2
La
Lanthanum is the most reactive of the rare earth metals
Fysikalske egenskaper
Fase
Fast stoff
Tetthet
6,145 g/cm3
Smeltepunkt
1193,15 K | 920 °C | 1688 °F
Kokepunkt
3737,15 K | 3464 °C | 6267,2 °F
Smeltevarme
6,2 kJ/mol
Fordampningsvarme
400 kJ/mol
Spesifikk varmekapasitet
0,195 J/g·K
Forekomst i jordskorpa
0,0034%
Forekomst i universet
2×10-7%
Pure
Bildekreditter: Images-of-elements
Pure lanthanum
CAS Number
7439-91-0
PubChem CID Number
23926
Atomegenskaper
Atomradius
187 pm
Kovalent radius
207 pm
Elektronegativitet
1,1 (Pauling-skalaen)
Ioniseringsenergi
5,5769 eV
Molart volum
22,5 cm3/mol
Termisk ledningsevne
0,135 W/cm·K
Oksidasjonstilstander
2, 3
Bruksområder
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.
Lanthanum and its compounds are considered to be moderately toxic
Isotoper
Stabile isotoper
139La
Ustabile isotoper
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