Tellurium (Te)
Element 52 · Metalloid · Solid at 25 °C · Group 16, Period 5
Tellurium pairs with cadmium in CdTe thin-film solar panels, and traces of it make steel and copper easier to machine.
On the periodic table, tellurium sits in group 16 — the chalcogens (oxygen group) — in period 5. 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 tellurium
| Atomic number (Z) | 52 |
|---|---|
| Symbol | Te |
| Atomic mass | 127.60 |
| Category | Metalloid |
| Group | 16 |
| Period | 5 |
| Block | p-block |
| Metal / nonmetal | Metalloid |
| State at 25 °C | Solid |
| Electron configuration | [Kr] 4d10 5s2 5p4 |
| Electronegativity (Pauling) | 2.1 |
| Melting point | 449.51 °C (722.66 K / 841.12 °F) |
| Boiling point | 988 °C (1,261.15 K / 1,810.4 °F) |
| Density | 6.232 g/cm³ |
Position in the periodic table
Tellurium shares group 16 — the chalcogens (oxygen group) with Oxygen (O), Sulfur (S), Selenium (Se), Polonium (Po), Livermorium (Lv). 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
Tellurium melts at 449.51 °C (722.66 K / 841.12 °F) and boils at 988 °C (1,261.15 K / 1,810.4 °F), giving it a liquid range of about 538.5 °C at standard pressure.
Its density is 6.232 g/cm³.
See also: the interactive periodic table, how to read the periodic table, metals, nonmetals & metalloids.