Germanium (Ge)
Element 32 · Metalloid · Solid at 25 °C · Group 14, Period 4
Germanium powered the first transistors before silicon took over, and it still serves in fiber-optic systems and infrared optics.
On the periodic table, germanium sits in group 14 — the carbon group — in period 4. It is one of 6 elements classified as a metalloid, and at room temperature (25 °C) it is a solid.
Metalloids line the zig-zag “staircase” between the metals and nonmetals and behave a bit like both: they look metallic but are brittle and conduct electricity only moderately well. That in-between conductivity — a semiconductor's — is exactly what modern electronics is built on.
Properties of germanium
| Atomic number (Z) | 32 |
|---|---|
| Symbol | Ge |
| Atomic mass | 72.630 |
| Category | Metalloid |
| Group | 14 |
| Period | 4 |
| Block | p-block |
| Metal / nonmetal | Metalloid |
| State at 25 °C | Solid |
| Electron configuration | [Ar] 3d10 4s2 4p2 |
| Electronegativity (Pauling) | 2.01 |
| Melting point | 938.25 °C (1,211.4 K / 1,720.85 °F) |
| Boiling point | 2,833 °C (3,106.15 K / 5,131.4 °F) |
| Density | 5.323 g/cm³ |
Position in the periodic table
Germanium shares group 14 — the carbon group with Carbon (C), Silicon (Si), Tin (Sn), Lead (Pb), Flerovium (Fl). Elements in the same group have the same number of outer electrons, so they tend to behave alike chemically — comparing them is one of the fastest ways to see periodic trends in action.
Physical properties
Germanium melts at 938.25 °C (1,211.4 K / 1,720.85 °F) and boils at 2,833 °C (3,106.15 K / 5,131.4 °F), giving it a liquid range of about 1,894.8 °C at standard pressure.
Its density is 5.323 g/cm³.
See also: the interactive periodic table, how to read the periodic table, metals, nonmetals & metalloids.