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| Holmium | Holmium | Holmij | Olmio | Holmium | ||||||||||||||||||||
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Ho Holmium |
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- Holmium was discovered by Per Theodore Cleve (Sweden) in 1879. The origin of the name comes from the Greek word Holmia meaning Stockholm. It is fairly soft, malleable, lustrous, silvery metal. Reacts slowly with oxygen and water. Dissolves in acids. Can react violently with air or halogens.
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TRANSITION ELEMENT: LANTHANIDE | |
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| Relative atomic mass: | 164.93032(2) | Electronic configuration: | [Xe] 4f11 6s2 |
| Formal oxidation number: | +3 | Electronegativities: | 1.23 |
| Thermal conductivity: | 16.2 W m-1 K-1 | Electrical resistivity (20 °C): | 87 μΩcm |
| Atomic radius: | 174.3 pm | Standard state (20 °C): | solid |
| Density (g dm-3): | 8795 (298 K) | Molar volume (cm3 mol-1): | 18.75 (298 K) |
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THERMAL PROPERTIES | |
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| Melting point: | 1474 °C | Heat of fusion: | 17.2 kJ mol-1 |
| Boiling point: | 2700 °C | Heat of vaporization: | 303 kJ mol-1 |
| Critical temperature: | 7297 °C | Heat of atomization: | 302.63 kJ mol-1 |
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IONIZATION ENERGIES AND ABUNDANCE | |
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| 1st ionization energy: | 580.99 kJ mol-1 | Abundance of element (air): | - ppm |
| 2nd ionization energy: | 1138.54 kJ mol-1 | Abundance of element (Earth's crust): | 0.78 ppm |
| 3rd ionization energy: | 2203.74 kJ mol-1 | Abundance of element (oceans): | 0.00000008 ppm |
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ISOTOPES | |
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Isotopes | Relative atomic mass | Abundance (%) |
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165Ho | 164.930319(3) | 100 |
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MINERALS AND USES | |
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- Holmium occurs in gadolinite. Most often from monazite sand. It has very few practical applications; however, it has some unusual magnetic properties that offer some hope for future applications. The price of 99.9 % pure holmium pieces is 348.50 € for 25 g.
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REDUCTION POTENTIALS | |
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Balanced half-reaction | Eo / V | Annotation |
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