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The symbol for Praseodymium is Pr

Symbol For Praseodymium: Pr
Group: Rare Earth
Atomic Number of Praseodymium: 59
Atomic Weight of Praseodymium: 140.90765


Electron Shells: 2,8,18,21,8,2
Orbital Electrons: [Xe] 4f3 6s2
Valence Electrons: 3


Crystal Structure of Praseodymium: Hexagonal
Melting Point of Praseodymium: 931°C
Boiling Point of Praseodymium: 3520°C
Electronegativity of Praseodymium: 1.13
Covalent Radius of Praseodymium: 1.65 Å
Ionic Radius of Praseodymium: 1.13 (+3) Å
Atomic Radius of Praseodymium: 2.67 Å
1st Ionization Potential of Praseodymium: 5.464 V
2nd Ionization Potential of Praseodymium: 10.551 V
3rd Ionization Potential of Praseodymium: 21.62 V
Density of Praseodymium at 293 Degrees Kelvin: 6.77 g/cm³
Electron Conductivity of Praseodymium: 0.0148 10^6/cm ohm
Thermal Conductivity of Praseodymium:0.125 W/cmK

Discovered By: C.F. Aver von Welsbach
Year Discoved: 1885
Location: Austria
Name Origin: Greek: prasios and didymos (green twin); from its green salts.

Combined Array for Research in Millimeter-wave Astronomy (CARMA) | Owens Valley Radio Observatory, Big Pine, California, USA

Telescopes of The World

Name of Telescope: Combined Array for Research in Millimeter-wave Astronomy (CARMA)
Location of Telescope: Owens Valley Radio Observatory, Big Pine, California, USA
Frequency Range of Telescope: 75?345 GHz
Comments: Heterogeneous interferometer array composed of 6 10-m elements, 9 6-m elements, and 8 3.5-m elements covering frequencies ranging from 27?36 GHz, 80?115 GHz, and 215?265 GHz. Operated by joint agreements between Radio Astronomy Laboratory University of California, Berkeley, Caltech, University of Maryland, College Park, University of Illinois, Urbana-Champaign, and the University of Chicago.