Praseodym

59
Pr
Grupp
n/a
Period
6
Block
f
Protoner
Elektroner
Neutroner
59
59
82
Generella Egenskaper
Atomnummer
59
Atommassa
140,90765
Masstal
141
Kategori
Lantanoider
Färg
Silver
Radioaktiv
Nej
From the Greek word prasios, green, and didymos, twin
Kristallstruktur
Enkelt hexagonalt
Historia
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.
Elektroner per skal
2, 8, 18, 21, 8, 2
Elektronkonfiguration
[Xe] 4f3 6s2
Pr
Praseodymium is usually stored under a light mineral oil or sealed in glass
Fysikaliska Egenskaper
Aggregationstillstånd
Fast
Densitet
6,773 g/cm3
Smältpunkt
1208,15 K | 935 °C | 1715 °F
Kokpunkt
3793,15 K | 3520 °C | 6368 °F
Smältvärme
6,9 kJ/mol
Ångbildningsvärme
330 kJ/mol
Specifik värmekapacitet
0,193 J/g·K
Abundance in Earth's crust
0,00086%
Abundance in Universe
2×10-7%
Ultrapure
Bildkrediter: Images-of-elements
Ultrapure praseodymium pieces under argon
CAS Number
7440-10-0
PubChem CID Number
23942
Atomära Egenskaper
Atomradie
182 pm
Kovalent radie
203 pm
Elektronegativitet
1,13 (Paulingskalan)
Jonisationspotential
5,473 eV
Molvolym
20,8 cm3/mol
Värmeledningsförmåga
0,125 W/cm·K
Oxidationstillstånd
2, 3, 4
Användningsområden
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
Isotoper
Stabila isotoper
141Pr
Instabila isotoper
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