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Information valid for Pt-195 unless otherwise noted

Basic Information

Symbol: Pt
Atomic Number: 78
Mass: 195.078
Melting Point: 1772.0 C
Boiling Point: 3827.0 C
Number of Protons/Electrons: 78
Number of Neutrons: 117
Classification: Transition Metal
Crystal Structure: Cubic
Density @ 293 K: 21.45 g/cm3
Color: silverish

Atomic Structure

[Bohr Model of Platinum]
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: 17
    Sixth Energy Level: 1


Isotope Half Life
Pt-188 10.2 days
Pt-190 6.0E11 years
Pt-191 2.96 days
Pt-192 Stable
Pt-193 60.0 years
Pt-193m 4.33 days
Pt-194 Stable
Pt-195 Stable
Pt-195m 4.02 days
Pt-196 Stable
Pt-197 18.3 hours
Pt-197m 1.59 hours
Pt-198 Stable


Date of Discovery: 1735
Discoverer: Julius Scaliger
Name Origin: From the Spanish word platina (little silver)
Uses: jewelry, containers, catalyst
Obtained From: platinum ores