Praseodim

59
Pr
Skupina
n/a
Perioda
6
Blok
f
Protons
Electrons
Neutrons
59
59
82
General Properties
Vrstno število
59
Atomska teža
140,90765
Mass Number
141
Kategorija
Lantanoidi
Barva
Silver
Radioactive
Ne
From the Greek word prasios, green, and didymos, twin
Kristalna struktura
Heksagonalna
Zgodovina
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.
Electrons per shell
2, 8, 18, 21, 8, 2
Razporeditev elektronov
[Xe] 4f3 6s2
Pr
Praseodymium is usually stored under a light mineral oil or sealed in glass
Physical Properties
Faza snovi
Trdnina
Gostota
6,773 g/cm3
Tališče
1208,15 K | 935 °C | 1715 °F
Vrelišče
3793,15 K | 3520 °C | 6368 °F
Talilna toplota
6,9 kJ/mol
Izparilna toplota
330 kJ/mol
Toplotna kapaciteta
0,193 J/g·K
Abundance in Earth's crust
0,00086%
Abundance in Universe
2×10-7%
Ultrapure
Zasluge za slike: Images-of-elements
Ultrapure praseodymium pieces under argon
CAS Number
7440-10-0
PubChem CID Number
23942
Atomic Properties
Atomski polmer
182 pm
Kovalentni polmer
203 pm
Elektronegativnost
1,13 (Paulingova lestvica)
Ionization Potential
5,473 eV
Atomic Volume
20,8 cm3/mol
Toplotna prevodnost
0,125 W/cm·K
Oksidacijska stanja
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