59
Pr
Praseodymium
140.907662
Praseodymium
LANTHANIDE
Bohr Model: Electrons arranged in energy shells around the nucleus.
Praseodymium is a chemical element with symbol Pr and atomic number 59. Praseodymium is a soft, silvery, malleable and ductile metal in the lanthanide group. It is valued for its magnetic, electrical, chemical, and optical properties.
Quick Facts
Atomic Number 59
Period 6
Group 5
Phase Solid
Appearance grayish white
About Lanthanides
Lanthanides are shiny metallic elements with atomic numbers 57–71. They are often called 'rare-earth elements' and are used in magnets and lasers.
History
Discovered By Carl Auer von Welsbach
Named By Unknown
Physical Properties
Atomic Mass 140.907662
Density 6.77 g/L
Molar Heat 27.2 J/(mol·K)
Phase Transition (Melting & Boiling Points)
Praseodymium melts at 1208 K and boils at 3403 K.
Atomic Properties
Electron Config [Xe] 4f3 6s2
Electronegativity 1.13
Electron Affinity 93 kJ/mol
Ionization Energy 527 kJ/mol
Orbital Filling Diagram
This diagram visualizes electron configuration according to the Aufbau principle and Hund's rule.
Boxes represent orbitals (s, p, d, f), while arrows indicate electrons with spin up or down.
Electrons fill lower energy levels first and occupy orbitals singly before pairing.
Photograph
External Resources
Study Guide
Atomic Number
The number of protons in the nucleus, which defines the element.
Atomic Mass
The average mass of an atom, including protons and neutrons.
Electronegativity
A measure of how strongly an atom attracts electrons in a bond.
Ionization Energy
The energy required to remove an electron from an atom.
Electron Config
The arrangement of electrons in the atom's energy shells.