Tellurium (Te)

Tellurium is a chemical element of the periodic table with chemical symbol Te and atomic number 52 with an atomic weight of 127.603 u and is classed as metalloid and is part of group 16 (oxygen group). Tellurium is solid at room temperature.

Antimony Periodic table Iodine

Tellurium in the periodic table

Symbol	Te
Atomic number	52
Group	16 (Oxygen group)
Period	5
Block	p
Classification	Metalloid

Appearance	-
Color	Silver

Number of protons	52 p⁺
Number of neutrons	76 n⁰
Number of electrons	52 e^-

From Wikipedia, the free encyclopediaTellurium is a chemical element with symbol Te and atomic number 52. It is a brittle, mildly toxic, rare, silver-white metalloid. Tellurium is chemically related to selenium and sulfur.

Physical properties

Phase at STP	Solid
Density	6.24 g/cm³
Atomic weight	127.603 u

Thermal properties

Melting point	722.66 K 449.51 °C 841.118 °F
Boiling point	1261 K 987.85 °C 1810.13 °F
Heat of vaporization	50.63 kJ/mol

Atomic properties

Electronegativity (Pauling Scale)	2.1
Electron affinity	190.161 kJ/mol
Oxidation states	−2, −1, +1, +2, +3, +4, +5, +6 (a mildly acidic oxide)
Ionization energies	869.3 kJ/mol 1790 kJ/mol 2698 kJ/mol 3610 kJ/mol 5668 kJ/mol 6820 kJ/mol 13200 kJ/mol

Electron configuration for tellurium

Electron configuration

Shorthand configuration

[Kr] 4d¹⁰ 5s² 5p⁴

Electron configuration

Full configuration

1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 5s² 5p⁴

Electron configuration chart

1s²
2s²	2p⁶
3s²	3p⁶	3d¹⁰
4s²	4p⁶	4d¹⁰
5s²	5p⁴

Electrons per shell

2, 8, 18, 18, 6

Valence electrons

6

Valency electrons

2,4,6

Bohr model

Figure: Shell diagram of Tellurium (Te) atom.

Orbital Diagram

1s
2s	2p
3s	3p	3d
4s	4p	4d
5s	5p

The history of Tellurium

Discovery	Franz-Joseph Müller von Reichenstein (1782)
First isolation	Martin Heinrich Klaproth
Named by	Martin Heinrich Klaproth (1798)
Discovery of tellurium Tellurium (Latin tellus meaning "earth") was discovered in the 18th century in a gold ore from the mines in Kleinschlatten (today Zlatna), near today's city of Alba Iulia, Romania. In 1782 Franz-Joseph Müller von Reichenstein, who was then serving as the Austrian chief inspector of mines in Transylvania, concluded that the ore did not contain antimony but was bismuth sulfide. The following year, he reported that this was erroneous and that the ore contained mostly gold and an unknown metal very similar to antimony. After a thorough investigation that lasted three years and included more than fifty tests, Müller determined the specific gravity of the mineral and noted that when heated, the new metal gives off a white smoke with a radish-like odor; that it imparts a red color to sulfuric acid; and that when this solution is diluted with water, it has a black precipitate. Nevertheless, he was not able to identify this metal and gave it the names aurum paradoxum (paradoxical gold) and metallum problematicum (problem metal), because it did not exhibit the properties predicted for antimony. In 1789, a Hungarian scientist, Pál Kitaibel, discovered the element independently in an ore from Deutsch-Pilsen that had been regarded as argentiferous molybdenite, but later he gave the credit to Müller. In 1798, it was named by Martin Heinrich Klaproth, who had earlier isolated it from the mineral calaverite.

Periodic table history

Identifiers

List of unique identifiers for Tellurium in various chemical registry databases

CAS Number	13494-80-9
ChemSpider ID	4885717
EC number	236-813-4
PubChem CID Number	6327182