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Information valid for Os-190 unless otherwise noted

Basic Information

Symbol: Os
Atomic Number: 76
Mass: 190.23
Melting Point: 3045.0 C
Boiling Point: 5027.0 C
Number of Protons/Electrons: 76
Number of Neutrons: 114
Classification: Transition Metal
Crystal Structure: Hexagonal
Density @ 293 K: 22.4 g/cm3
Color: black

Atomic Structure

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

  1. First Energy Level: 2
    Second Energy Level: 8
    Third Energy Level: 18
    Fourth Energy Level: 32
    Fifth Energy Level: 14
    Sixth Energy Level: 2


Isotope Half Life
Os-184 Stable
Os-185 93.6 days
Os-186 2.0E15 years
Os-187 Stable
Os-188 Stable
Os-189 Stable
Os-190 Stable
Os-190m 9.9 minutes
Os-191 15.4 days
Os-191m 13.1 hours
Os-192 Stable
Os-193 30.5 hours
Os-194 6.0 years


Date of Discovery: 1804
Discoverer: Smithson Tenant
Name Origin: From the Greek word osmŽ (odor)
Uses: tip gold pen points, instrument pivots, electrical light filaments
Obtained From: ores that contain platinum