63
Eu
Europium
151.9641
Europium
LANTHANIDE
Bohr Model: Electrons arranged in energy shells around the nucleus.
Europium is a chemical element with symbol Eu and atomic number 63. It was isolated in 1901 and is named after the continent of Europe. It is a moderately hard, silvery metal which readily oxidizes in air and water.
Quick Facts
Atomic Number 63
Period 6
Group 9
Phase Solid
Appearance Unknown
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 Eugène-Anatole Demarçay
Named By Unknown
Physical Properties
Atomic Mass 151.9641
Density 5.264 g/L
Molar Heat 27.66 J/(mol·K)
Phase Transition (Melting & Boiling Points)
Europium melts at 1099 K and boils at 1802 K.
Atomic Properties
Electron Config [Xe] 4f7 6s2
Electronegativity 1.2
Electron Affinity 11.2 kJ/mol
Ionization Energy 547.1 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.