Praseodym

59
Pr
Gruppe
n/a
Periode
6
Blokk
f
Protons
Electrons
Neutrons
59
59
82
Generelle eigenskapar
Atomnummer
59
Atommasse
140,90765
Mass Number
141
Kategori
Lantanid
Farge
Silver
Radioactive
Nei
From the Greek word prasios, green, and didymos, twin
Krystallstruktur
Simple Hexagonal
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
Abundance in Earth's crust
0,00086%
Abundance in Universe
2×10-7%
Ultrapure
Image Credits: Images-of-elements
Ultrapure praseodymium pieces under argon
CAS Number
7440-10-0
PubChem CID Number
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
Applications
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
Isotopes
Stable Isotopes
141Pr
Unstable Isotopes
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