Erbium at Chemical Elements.com 


 

Basic Information


Name: Erbium
Symbol: Er
Atomic Number: 68
Atomic Mass: 167.26 amu
Melting Point: 1522.0 °C (1795.15 °K, 2771.6 °F)
Boiling Point: 2510.0 °C (2783.15 °K, 4550.0 °F)
Number of Protons/Electrons: 68
Number of Neutrons: 99
Classification: Rare Earth
Crystal Structure: Hexagonal
Density @ 293 K: 8.795 g/cm3
Color: grayish


Atomic Structure

[Bohr Model of Erbium]  
Number of Energy Levels: 6

    First Energy Level: 2
    Second Energy Level: 8
    Third Energy Level: 18
    Fourth Energy Level: 30
    Fifth Energy Level: 8
    Sixth Energy Level: 2

Isotopes

Isotope Half Life
Er-162 Stable
Er-164 Stable
Er-166 Stable
Er-167 Stable
Er-168 Stable
Er-169 9.4 days
Er-170 Stable
Er-171 7.5 hours
Er-172 2.1 days

Facts


Date of Discovery: 1843
Discoverer: Carl Mosander
Name Origin: Ytterby (a town in Sweden)
Uses: ceramics
Obtained From: heavier rare earth minerals