68 Er Erbium 167.2593

Erbium

LANTHANIDE
Bohr Model: Electrons arranged in energy shells around the nucleus.

Erbium is a chemical element in the lanthanide series, with symbol Er and atomic number 68. A silvery-white solid metal when artificially isolated, natural erbium is always found in chemical combination with other elements on Earth. As such, it is a rare earth element which is associated with several other rare elements in the mineral gadolinite from Ytterby in Sweden, where yttrium, ytterbium, and terbium were discovered.

Quick Facts

Atomic Number 68
Period 6
Group 14
Phase Solid
Appearance silvery 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 Gustaf Mosander
Named By Unknown

Physical Properties

Atomic Mass 167.2593
Density 9.066 g/L
Molar Heat 28.12 J/(mol·K)
Phase Transition (Melting & Boiling Points)

Erbium melts at 1802 K and boils at 3141 K.

Atomic Properties

Electron Config [Xe] 4f12 6s2
Electronegativity 1.24
Electron Affinity 30.1 kJ/mol
Ionization Energy 589.3 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

Image of Erbium Source: Wikipedia

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.