This semimetal is named after the country Germany, and this is because it was discovered there. Thus, in 1886, the chemist Clemens A. Winkler discovered germanium, almost 20 years after the Russian chemist Dimitri Mendeleev predicted its existence and properties. Germanite is a germanium-rich mineral, but this element is mainly extracted from silver, copper and lead ores. One of its compounds, germanium oxide, GeO2, is used in the lenses of wide-angle cameras. It is also used in some microchips and in various automotive sensors that aid navigation.
Summary of properties (Ge)
Atomic weight | 72.630(8) |
Discoverer (year) | Winkler, Clemens A. (1886) |
Natural form | non-metal solid (face centered cubic) |
Electron configuration | [Ar] 3d10 4s2 4p2 |
Melting point (ºC) | 937 |
Boiling point (ºC) | 2830 |
Abundance in earth's crust (ppm) | 1.5 |
Isotope (abundance) | 70Ge (20.52), 72Ge (27.45), 73Ge (7.76), 74Ge (36.52), 76Ge (7.75) |
Density g/cm3 | 5.32 |
Van der Waals radius (pm) | 211 |
Covalent radius (pm) | 120 |
Electronegativity (Pauling) | 2.18 |
Vaporization enthalpy (kJ/mol) | 334.00 |
Enthalpy of fusion (kJ/mol) | 36.94 |
Specific heat capacity (J/g·K) at 25ºC and 1 atm | 0.32 |
Thermal conductivity (W/cm·K) at 25ºC and 1 atm | 0.600 |
Oxidation state | +4, +2 |
Electron affinity (eV) | 1.23 |
1st Ionization potential (eV) | 7.8994 |