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72 - Hafnium transition metal

Atomic Mass (u)

178.49

Density (g/cm³)

13.31

Phase

Solid

Year of Discovery

1923
HafniumHfElectron 1Electron 2Electron 1Electron 2Electron 3Electron 4Electron 5Electron 6Electron 7Electron 8Electron 1Electron 2Electron 3Electron 4Electron 5Electron 6Electron 7Electron 8Electron 9Electron 10Electron 11Electron 12Electron 13Electron 14Electron 15Electron 16Electron 17Electron 18Electron 1Electron 2Electron 3Electron 4Electron 5Electron 6Electron 7Electron 8Electron 9Electron 10Electron 11Electron 12Electron 13Electron 14Electron 15Electron 16Electron 17Electron 18Electron 19Electron 20Electron 21Electron 22Electron 23Electron 24Electron 25Electron 26Electron 27Electron 28Electron 29Electron 30Electron 31Electron 32Electron 1Electron 2Electron 3Electron 4Electron 5Electron 6Electron 7Electron 8Electron 9Electron 10Electron 1Electron 2

Hafnium is a chemical element with symbol Hf and atomic number 72. A lustrous, silvery gray, tetravalent transition metal, hafnium chemically resembles zirconium and is found in zirconium minerals. Its existence was predicted by Dmitri Mendeleev in 1869, though it was not identified until 1923, making it the penultimate stable element to be discovered (rhenium was identified two years later).

72 Atomic Number
178.49 Atomic Mass (u)
2500.15 Melting Point (K)
4876 Boiling Point (K)
13.31 Density (solid: g/cm³, gas: g/liter)
2.2 Atomic Radius (Å)
1.75 Covalent Radius (Å)
1.3 Electronegativity
6.83 First Ionization Energy (eV)
17.18 Electron Affinity
6 Number of Shells
2, 8, 18, 32, 10, 2 Electron Shell Occupations
0.14 Specific Heat (J/g)