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Information valid for Hf-178 unless otherwise noted

Basic Information

Symbol: Hf
Atomic Number: 72
Mass: 178.49
Melting Point: 2150.0 C
Boiling Point: 5400.0 C
Number of Protons/Electrons: 72
Number of Neutrons: 106
Classification: Transition Metal
Crystal Structure: Hexagonal
Density @ 293 K: 13.2 g/cm3
Color: Silver

Atomic Structure

[Bohr Model of Hafnium]
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: 10
    Sixth Energy Level: 2


Isotope Half Life
Hf-172 1.9 years
Hf-174 2.0E15 years
Hf-175 70.0 days
Hf-176 Stable
Hf-177 Stable
Hf-178 Stable
Hf-179 Stable
Hf-180 Stable
Hf-182 Stable
Hf-182 Stable


Date of Discovery: 1923
Discoverer: Dirk Coster
Name Origin: From the Latin word Hafnia (Copenhagen)
Uses: nuclear reactors
Obtained From: zircon