Tellurium Element Information, Facts, Properties, Trends, Uses, Comparison with other elements
Tellurium 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.
It belongs to group 16 of the periodic table having trivial name chalcogens. You can also download Printable Periodic Table of Elements Flashcards for Tellurium in a PDF format.
Tellurium Facts
Read key information and facts about element Tellurium
| Name | Tellurium |
| Atomic Number | 52 |
| Atomic Symbol | Te |
| Atomic Weight | 127.6 |
| Phase | Solid |
| Color | Silver |
| Appearance | - |
| Classification | Metalloid |
| Natural Occurance | Primordial |
| Group in Periodic Table | 16 |
| Group Name | oxygen family |
| Period in Periodic Table | period 5 |
| Block in Periodic Table | p-block |
| Electronic Configuration | [Kr] 4d10 5s2 5p4 |
| Electronic Shell Structure (Electrons per shell) | 2, 8, 18, 18, 6 |
| Melting Point | 722.66 K |
| Boiling Point | 1261 K |
| CAS Number | CAS13494-80-9 |
How to Locate Tellurium on Periodic Table
Periodic table is arranged by atomic number, number of protons in the nucleus which is same as number of electrons. The atomic number increases from left to right. Periodic table starts at top left ( Atomic number 1) and ends at bottom right (atomic number 118). Therefore you can directly look for atomic number 52 to find Tellurium on periodic table.
Another way to read periodic table and locate an element is by using group number (column) and period number (row). To locate Tellurium on periodic table look for cross section of group 16 and period 5 in the modern periodic table.
Tellurium History
The element Tellurium was discovered by F.-J.M. von Reichenstein in year 1782 in Romania. Tellurium was first isolated by H. Klaproth in . Tellurium derived its name from Latin tellus, meaning 'earth'.
| Discovered By | F.-J.M. von Reichenstein |
| Discovery Date | 1782 in Romania |
| First Isolation | |
| Isolated by | H. Klaproth |
Muller observed it as an impurity in gold ores from Transylvania.
Tellurium Uses
Tellurium permits better copper and stainless steel machinability. It is used as a basic component of cast iron and blasting caps.
Tellurium Presence: Abundance in Nature and Around Us
The table below shows the abundance of Tellurium in Universe, Sun, Meteorites, Earth's Crust, Oceans and Human Body.
| ppb by weight (1ppb =10^-7 %) | ppb by atoms (1ppb =10^-7 %) | |
|---|---|---|
| Abundance in Universe | 9 | 0.09 |
| Abundance in Sun | - | - |
| Abundance in Meteorites | 2100 | 300 |
| Abundance in Earth's Crust | 1.0 | 0.2 |
| Abundance in Oceans | - | - |
| Abundance in Humans | - | - |
Crystal Structure of Tellurium
The solid state structure of Tellurium is Simple Trigonal.
The Crystal structure can be described in terms of its unit Cell. The unit Cells repeats itself in three dimensional space to form the structure.
Unit Cell Parameters
The unit cell is represented in terms of its lattice parameters, which are the lengths of the cell edges Lattice Constants (a, b and c)
| a | b | c |
|---|---|---|
| 445.72 pm | 445.72 pm | 592.9 pm |
and the angles between them Lattice Angles (alpha, beta and gamma).
| alpha | beta | gamma |
|---|---|---|
| π/2 | π/2 | 2 π/3 |
The positions of the atoms inside the unit cell are described by the set of atomic positions ( xi, yi, zi) measured from a reference lattice point.
The symmetry properties of the crystal are described by the concept of space groups. All possible symmetric arrangements of particles in three-dimensional space are described by the 230 space groups (219 distinct types, or 230 if chiral copies are considered distinct.
| Space Group Name | P3121 |
| Space Group Number | 152 |
| Crystal Structure | Simple Trigonal |
| Number of atoms per unit cell |
The number of atoms per unit cell in a simple cubic, face-centered cubic and body-centred cubic are 1,4,2 respectively.
Tellurium Atomic and Orbital Properties
Tellurium atoms have 52 electrons and the electronic shell structure is [2, 8, 18, 18, 6] with Atomic Term Symbol (Quantum Numbers) 3P2.
| Atomic Number | 52 |
| Number of Electrons (with no charge) | 52 |
| Number of Protons | 52 |
| Mass Number | 128 |
| Number of Neutrons | 76 |
| Shell structure (Electrons per energy level) | 2, 8, 18, 18, 6 |
| Electron Configuration | [Kr] 4d10 5s2 5p4 |
| Valence Electrons | 5s2 5p4 |
| Valence (Valency) | 6 |
| Main Oxidation States | -2, 2, 4, 6 |
| Oxidation States | -2, -1, 0, 1, 2, 3, 4, 5, 6 |
| Atomic Term Symbol (Quantum Numbers) | 3P2 |
Bohr Atomic Model of Tellurium - Electrons per energy level
| n | s | p | d | f |
|---|
Ground State Electronic Configuration of Tellurium - neutral Tellurium atom
Abbreviated electronic configuration of Tellurium
The ground state abbreviated electronic configuration of Neutral Tellurium atom is [Kr] 4d10 5s2 5p4. The portion of Tellurium configuration that is equivalent to the noble gas of the preceding period, is abbreviated as [Kr]. For atoms with many electrons, this notation can become lengthy and so an abbreviated notation is used. This is important as it is the Valence electrons 5s2 5p4, electrons in the outermost shell that determine the chemical properties of the element.
Unabbreviated electronic configuration of neutral Tellurium
Complete ground state electronic configuration for the Tellurium atom, Unabbreviated electronic configuration
1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p4
Electrons are filled in atomic orbitals as per the order determined by the Aufbau principle, Pauli Exclusion Principle and Hund’s Rule.
As per the Aufbau principle the electrons will occupy the orbitals having lower energies before occupying higher energy orbitals. According to this principle, electrons are filled in the following order: 1s, 2s, 2p, 3s, 3p, 4s, 3d, 4p, 5s, 4d, 5p, 6s, 4f, 5d, 6p, 7s, 5f, 6d, 7p…
The Pauli exclusion principle states that a maximum of two electrons, each having opposite spins, can fit in an orbital.
Hund's rule states that every orbital in a given subshell is singly occupied by electrons before a second electron is filled in an orbital.
Atomic Structure of Tellurium
Tellurium atomic radius is 123 pm, while it's covalent radius is 135 pm.
| Atomic Radius Calculated | 123 pm(1.23 Å) |
| Atomic Radius Empirical | 140 pm (1.4 Å) |
| Atomic Volume | 20.449 cm3/mol |
| Covalent Radius | 135 pm (1.35 Å) |
| Van der Waals Radius | 206 pm |
| Neutron Cross Section | 5.4 |
| Neutron Mass Absorption | 0.0013 |
Spectral Lines of Tellurium - Atomic Spectrum of Tellurium
A spectral line is a dark or bright line in an otherwise uniform and continuous spectrum, resulting from an excess or deficiency of photons in a narrow frequency range, compared with the nearby frequencies. Spectral lines are often used to identify atoms and molecules.
Spectral lines are the result of interaction between a quantum system and a single photon. A spectral line may be observed either as an emission line or an absorption line.
Spectral lines are highly atom-specific, and can be used to identify the chemical composition of any medium. Several elements, including helium, thallium, and caesium, were discovered by spectroscopic means. They are widely used to determine the physical conditions of stars and other celestial bodies that cannot be analyzed by other means.
Emission spectrum of Tellurium
Absorption spectrum of Tellurium
Tellurium Chemical Properties: Tellurium Ionization Energies and electron affinity
The electron affinity of Tellurium is 190.2 kJ/mol.
| Valence | 6 |
| Electronegativity | 2.1 |
| ElectronAffinity | 190.2 kJ/mol |
Ionization Energy of Tellurium
Ionization energy is the amount of energy required to remove an electron from an atom or molecule.in chemistry, this energy is expresed in kilocalories per mole (kcal/mol) or kilojoules per mole (kJ/mol).
Refer to table below for Ionization energies of Tellurium
| Ionization energy number | Enthalpy - kJ/mol |
|---|---|
| 1st | 869.3 |
| 2nd | 1790 |
| 3rd | 2698 |
| 4th | 3610 |
| 5th | 5668 |
| 6th | 6820 |
| 7th | 13200 |
Tellurium Physical Properties
Refer to below table for Tellurium Physical Properties
| Density | 6.24 g/cm3(when liquid at m.p density is $5.7 g/cm3) |
| Molar Volume | 20.449 cm3/mol |
Elastic Properties
| Young Modulus | 43 |
| Shear Modulus | 16 GPa |
| Bulk Modulus | 65 GPa |
| Poisson Ratio | - |
Hardness of Tellurium - Tests to Measure of Hardness of Element
| Mohs Hardness | 2.25 MPa |
| Vickers Hardness | - |
| Brinell Hardness | 180 MPa |
Tellurium Electrical Properties
Electrical resistivity measures element's electrical resistance or how strongly it resists electric current.The SI unit of electrical resistivity is the ohm-metre (Ω⋅m). While Electrical conductivity is the reciprocal of electrical resistivity. It represents a element's ability to conduct electric current. The SI unit of electrical conductivity is siemens per metre (S/m).
Tellurium is a Semiconductor. Refer to table below for the Electrical properties of Tellurium
| Electrical conductors | Semiconductor |
| Electrical Conductivity | 10000 S/m |
| Resistivity | 0.0001 m Ω |
| Superconducting Point | - |
Tellurium Heat and Conduction Properties
| Thermal Conductivity | 3 W/(m K) |
| Thermal Expansion | - |
Tellurium Magnetic Properties
| Magnetic Type | Diamagnetic |
| Curie Point | - |
| Mass Magnetic Susceptibility | -3.9e-9 m3/kg |
| Molar Magnetic Susceptibility | -4.98e-10 m3/mol |
| Volume Magnetic Susceptibility | -0.0000243 |
Optical Properties of Tellurium
| Refractive Index | 1.000991 |
Acoustic Properties of Tellurium
| Speed of Sound | 2610 m/s |
Tellurium Thermal Properties - Enthalpies and thermodynamics
Refer to table below for Thermal properties of Tellurium
| Melting Point | 722.66 K(449.51 °C, 841.118 °F) |
| Boiling Point | 1261 K(987.85 °C, 1810.130 °F) |
| Critical Temperature | - |
| Superconducting Point | - |
Enthalpies of Tellurium
| Heat of Fusion | 17.5 kJ/mol |
| Heat of Vaporization | 48 kJ/mol |
| Heat of Combustion | - |
Tellurium Isotopes - Nuclear Properties of Tellurium
Tellurium has 38 isotopes, with between 105 and 142 nucleons. Tellurium has 5 stable naturally occuring isotopes.
Isotopes of Tellurium - Naturally occurring stable Isotopes: 120Te, 122Te, 124Te, 125Te, 126Te.
| Isotope | Z | N | Isotope Mass | % Abundance | T half | Decay Mode |
|---|---|---|---|---|---|---|
| 105Te | 52 | 53 | 105 | Synthetic | ||
| 106Te | 52 | 54 | 106 | Synthetic | ||
| 107Te | 52 | 55 | 107 | Synthetic | ||
| 108Te | 52 | 56 | 108 | Synthetic | ||
| 109Te | 52 | 57 | 109 | Synthetic | ||
| 110Te | 52 | 58 | 110 | Synthetic | ||
| 111Te | 52 | 59 | 111 | Synthetic | ||
| 112Te | 52 | 60 | 112 | Synthetic | ||
| 113Te | 52 | 61 | 113 | Synthetic | ||
| 114Te | 52 | 62 | 114 | Synthetic | ||
| 115Te | 52 | 63 | 115 | Synthetic | ||
| 116Te | 52 | 64 | 116 | Synthetic | ||
| 117Te | 52 | 65 | 117 | Synthetic | ||
| 118Te | 52 | 66 | 118 | Synthetic | ||
| 119Te | 52 | 67 | 119 | Synthetic | ||
| 120Te | 52 | 68 | 120 | 0.09% | Stable | N/A |
| 121Te | 52 | 69 | 121 | Synthetic | ||
| 122Te | 52 | 70 | 122 | 2.55% | Stable | N/A |
| 123Te | 52 | 71 | 123 | 0.89% | Stable | N/A |
| 124Te | 52 | 72 | 124 | 4.74% | Stable | N/A |
| 125Te | 52 | 73 | 125 | 7.07% | Stable | N/A |
| 126Te | 52 | 74 | 126 | 18.84% | Stable | N/A |
| 127Te | 52 | 75 | 127 | Synthetic | ||
| 128Te | 52 | 76 | 128 | 31.74% | Stable | |
| 129Te | 52 | 77 | 129 | Synthetic | ||
| 130Te | 52 | 78 | 130 | 34.08% | Stable | N/A |
| 131Te | 52 | 79 | 131 | Synthetic | ||
| 132Te | 52 | 80 | 132 | Synthetic | ||
| 133Te | 52 | 81 | 133 | Synthetic | ||
| 134Te | 52 | 82 | 134 | Synthetic | ||
| 135Te | 52 | 83 | 135 | Synthetic | ||
| 136Te | 52 | 84 | 136 | Synthetic | ||
| 137Te | 52 | 85 | 137 | Synthetic | ||
| 138Te | 52 | 86 | 138 | Synthetic | ||
| 139Te | 52 | 87 | 139 | Synthetic | ||
| 140Te | 52 | 88 | 140 | Synthetic | ||
| 141Te | 52 | 89 | 141 | Synthetic | ||
| 142Te | 52 | 90 | 142 | Synthetic |
Regulatory and Health - Health and Safety Parameters and Guidelines
The United States Department of Transportation (DOT) identifies hazard class of all dangerous elements/goods/commodities either by its class (or division) number or name. The DOT has divided these materials into nine different categories, known as Hazard Classes.
| DOT Numbers | 2811 |
| DOT Hazard Class | 6.1 |
NFPA 704 is a Standard System for the Identification of the Hazards of Materials for Emergency Response. NFPA is a standard maintained by the US based National Fire Protection Association.
The health (blue), flammability (red), and reactivity (yellow) rating all use a numbering scale ranging from 0 to 4. A value of zero means that the element poses no hazard; a rating of four indicates extreme danger.
| NFPA Fire Rating | 0 | Will not burn |
| NFPA Health Rating | 2 | Flash Points Above 37.8°C (100°F) not exceeding 93.3°C (200°F) |
| NFPA Reactivity Rating | 0 | Will not burn |
| NFPA Hazards |
| Autoignition Point | 340 °C |
| Flashpoint | - |
Database Search
List of unique identifiers to search the element in various chemical registry databases
| Database | Identifier number |
|---|---|
| CAS Number - Chemical Abstracts Service (CAS) | CAS13494-80-9 |
| RTECS Number | RTECSWY2625000 |
| CID Number | CID6327182 |
| Gmelin Number | - |
| NSC Number | - |
Compare Tellurium with other elements
Compare Tellurium with Group 16, Period 5 and Metalloid elements of the periodic table.
Compare Tellurium with all Group 16 elements
Compare Tellurium with all Period 5 elements
Compare Tellurium with all Metalloid elements
Frequently Asked Questions (FAQ)
Find the answers to the most frequently asked questions about Tellurium