Praseodym

59
Pr
Gruppe
i/t
Periode
6
Blokk
f
Proton
Elektron
Nøytron
59
59
82
Generelle eigenskapar
Atomnummer
59
Atommasse
140,90765
Massetal
141
Kategori
Lantanid
Farge
Sølv
Radioaktiv
Nei
From the Greek word prasios, green, and didymos, twin
Krystallstruktur
Enkel heksagonal
Historie
Praseodymium was first identified in 1885, in Vienna, by the Austrian chemist Carl Auer von Welsbach.

It was discovered in didymium, a substance incorrectly said by Carl Gustav Mosander to be a new element in 1841.

Pure metallic praseodymium was first produced in 1931.
Elektron per energinivå
2, 8, 18, 21, 8, 2
Elektronkonfigurasjon
[Xe] 4f3 6s2
Pr
Praseodymium is usually stored under a light mineral oil or sealed in glass
Fysiske eigenskapar
Tilstandsform
Fast stoff
Tettleik
6,773 g/cm3
Smeltepunkt
1208,15 K | 935 °C | 1715 °F
Kokepunkt
3793,15 K | 3520 °C | 6368 °F
Smeltevarme
6,9 kJ/mol
Fordampingsvarme
330 kJ/mol
Spesifikk varmekapasitet
0,193 J/g·K
Førekomst i jordskorpa
0,00086%
Førekomst i universet
2×10-7%
Ultrapure
Bilet­kreditering: Images-of-elements
Ultrapure praseodymium pieces under argon
CAS-nummer
7440-10-0
PubChem CID-nummer
23942
Atom eigenskapar
Atomradius
182 pm
Kovalent radius
203 pm
Elektronegativitet
1,13 (Paulings skala)
Ioniseringspotensial
5,473 eV
Molart volum
20,8 cm3/mol
Termisk konduktivitet
0,125 W/cm·K
Oksidasjonstrinn
2, 3, 4
Bruksområde
Praseodymium is used as an alloying agent with magnesium to create high-strength metals that are used in aircraft engines.

Misch metal, used in making cigarette lighters, contains about 5% praseodymium metal.

Praseodymium is used to make specialized yellow glass goggles for glass blowers and welders.
Praseodymium is considered to be moderately toxic
Isotopar
Stabile isotopar
141Pr
Ustabile isotopar
121Pr, 122Pr, 123Pr, 124Pr, 125Pr, 126Pr, 127Pr, 128Pr, 129Pr, 130Pr, 131Pr, 132Pr, 133Pr, 134Pr, 135Pr, 136Pr, 137Pr, 138Pr, 139Pr, 140Pr, 142Pr, 143Pr, 144Pr, 145Pr, 146Pr, 147Pr, 148Pr, 149Pr, 150Pr, 151Pr, 152Pr, 153Pr, 154Pr, 155Pr, 156Pr, 157Pr, 158Pr, 159Pr