32GeGermanium72.63 u
Germanium (Ge)
Germanium is a metalloid with atomic number 32, in period 4 and group 14 of the periodic table. Its atomic mass is 72.63 u and its electron configuration is [Ar] 3d¹⁰ 4s² 4p². Solid at 25 °C.
Key facts
| Atomic number | 32 |
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| Atomic mass | 72.63 u |
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| Category | Metalloid |
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| Period | 4 |
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| Group | 14 |
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| Block | p |
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| Electron configuration | [Ar] 3d¹⁰ 4s² 4p² |
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| Electrons per shell | 2, 8, 18, 4 |
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| Electronegativity (Pauling) | 2.01 |
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| Oxidation states | −4, −3, −2, −1, +1, +2, +3, +4common in bold |
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| State at 25 °C | Solid |
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| Melting point | 1211.4 K938.25 °C |
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| Boiling point | 3106 K2832.85 °C |
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| Density | 5.323 g/cm³ |
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Atomic properties
| First ionization energy | 7.899 eV |
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| Electron affinity | 130.3 kJ/mol |
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| Atomic radius | 122 pm |
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| Covalent radius | 120 pm |
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| Van der Waals radius | 211 pm |
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| Common ions | Ge⁴⁺ |
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| Protons, neutrons, electrons | 32, 41, 32 |
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Physical and thermal properties
| Molar volume | 13.63 cm³/mol |
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| Heat of fusion | 31.8 kJ/mol |
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| Heat of vaporization | 334 kJ/mol |
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| Specific heat | 321.4 J/(kg·K) |
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| Thermal conductivity | 60 W/(m·K) |
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| Thermal expansion | 6 × 10⁻⁶ K⁻¹ |
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| Mohs hardness | 6 |
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| Young’s modulus | --- |
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| Crystal structure | Face-centered cubic |
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| Magnetic type | Diamagnetic |
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Identification and history
| CAS number | 7440-56-4 |
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| Latin name | Germanium |
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| Discovered by | Clemens Winkler · 1886 |
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| Named by | --- |
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Natural isotopes
| Isotope | Mass (u) | Abundance |
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| 70Ge | 69.924249 | 20.52 % |
| 72Ge | 71.922076 | 27.45 % |
| 73Ge | 72.923459 | 7.76 % |
| 74Ge | 73.921178 | 36.52 % |
| 76Ge | 75.921403 | 7.75 % |
Data checked against PubChem (NIH), IUPAC, the NIST Atomic Spectra Database and the IAEA (NUBASE and AME), the same data you see in the app.
A dash (---) means there is no reliable published measurement. The app never makes one up.
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Periodic Table