Praseodymium (Pr)

Praseodymium is a chemical element with symbol Pr and atomic number 59. It is the third member of the lanthanide series and is traditionally considered to be one of the rare-earth metals.

Atomic Number

59

Atomic Mass

140.91 u

Category

lanthanide

Phase

solid

Density

6.77 g/cm³

Electron Shells

2, 8, 18, 21, 8, 2

Atomic Structure

Protons: 59 • Electrons: 59 • Neutrons: Varies by isotope

Electron Configuration: 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s² 4d¹⁰ 5p⁶ 6s² 4f³

Discovery

1885 • Carl Auer von Welsbach