Tellurium (Te): electron configuration, atomic mass and facts
Tellurium (Te) is element 52 of the periodic table, a metalloid in period 5, group 16. Its electron configuration is [Kr] 4d10 5s2 5p4, with electrons arranged in shells 2, 8, 18, 18, 6, and its standard atomic weight is 127.6 u.
▶ Watch Tellurium’s electrons orbit in the interactive periodic tableTellurium at a glance
| Symbol | Te |
|---|---|
| Atomic number | 52 |
| Atomic mass | 127.6 u |
| Category | Metalloid |
| Group | 16 |
| Period | 5 |
| Block | p-block |
| Electron configuration | 1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p4 |
| Noble-gas shorthand | [Kr] 4d10 5s2 5p4 |
| Electrons per shell | 2, 8, 18, 18, 6 |
| Outer-shell electrons | 6 |
| Electronegativity (Pauling) | 2.1 |
| State at 20 °C | solid |
Where is Tellurium on the periodic table?
Tellurium is in period 5, group 16, in the p-block. The period number matches its 5 electron shells, and the block names the subshell its last electrons fill. In the same group, Selenium sits directly above it and Polonium sits directly below it. Elements in one group have the same number of outer-shell electrons (6 here), which is why they react in similar ways.
How to work out the electron configuration of Tellurium
Put 52 electrons into subshells in order of rising energy, filling each before starting the next: 1s² (2), 2s² (4), 2p⁶ (10), 3s² (12), 3p⁶ (18), 4s² (20), 3d¹⁰ (30), 4p⁶ (36), 5s² (38), 4d¹⁰ (48), 5p⁴ (52). In shorthand, [Kr] stands for the 36 electrons of krypton, giving [Kr] 4d¹⁰ 5s² 5p⁴.
How electronegative is Tellurium?
Tellurium has a Pauling electronegativity of 2.1, ranking 27 of the 100 elements with a known value (fluorine is highest at 3.98). That is in the middle of the range.
Frequently asked questions
What is the electron configuration of Tellurium?
The electron configuration of Tellurium (Te) is 1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p4. In noble-gas shorthand it is written [Kr] 4d10 5s2 5p4.
How many electrons does Tellurium have in each shell?
Tellurium has 52 electrons arranged in shells as 2, 8, 18, 18, 6. It has 6 electrons in its outer shell.
What is the atomic mass of Tellurium?
The standard atomic weight of Tellurium is 127.6 u, so one mole of Tellurium atoms has a mass of about 127.6 g.
Is Tellurium a metal?
Tellurium is a metalloid: its properties sit between those of metals and nonmetals.
Explore nearby elements
More metalloids: Boron, Silicon, Germanium, Arsenic, Antimony. See all elements on the periodic table.