Thallium element (Tl) is in group 13 and period 6 of a periodic table. Thallium is in the p-block and it is classified as a post-transition element on the periodic table.
There is a lot more information related to thallium which is mentioned in the Information Table given below.
So let’s dive right into it!
Table of contents
- Thallium element (Information Table)
- Thallium element in Periodic table
- Facts about Thallium
- Properties of Thallium
- Uses of Thallium
Thallium Element (Information Table)
The important data related to thallium element is given in the table below.
|Appearance of thallium||Silvery gray appearance|
|Atomic number of thallium||81|
|Symbol of thallium||Tl|
|Atomic mass of thallium||204.38 u|
|Protons, Neutrons & Electrons in thallium||Protons: 81, Neutrons: 123, Electrons: 81|
|State of thallium (at STP)||Solid|
|Group number of thallium in periodic table||13|
|Period number of thallium in periodic table||6|
|Block of thallium in periodic table||p-block|
|Category of thallium||Post transition element (boron group)|
|Bohr model or Electrons per shell or Electrons arrangement in thallium||2, 8, 18, 32, 18, 3|
|Electron configuration of thallium||[Xe] 4f14 5d10 6s2 6p1|
|Orbital diagram of thallium|
|Valence electrons in thallium||3|
|Electronegativity of thallium (on pauling scale)||1.62|
|Atomic radius of thallium (van der Waals radius)||196 picometers|
|Density of thallium||11.85 g/cm3|
|1st ionization energy of thallium||6.108 eV|
|Main isotope of thallium||205Tl|
|Melting point of thallium||577 K or 304 °C or 579 °F|
|Boiling point of thallium||1746 K or 1473 °C or 2683 °F|
|Crystal structure of thallium||Hexagonal Close Packed (HCP)|
|Discovery of thallium||By William Crookes (in 1861)|
Also see: Interactive Periodic Table (It has rotating bohr models as well as many other details of all the 118 elements in a single periodic table).
Thallium element in Periodic table
The Thallium element (Tl) has the atomic number 81 and is located in group 13 and period 6. Thallium is a metal and it is classified as a post-transition element.
Click on above elements in the periodic table to see their information.
Facts about thallium
Here are a few interesting facts about thallium.
- William Crookes discovered thallium in the year 1861.
- Thallium was given its name from the Greek word “thallos”, meaning green shoot.
- The earth’s crust contains around 850 parts per billion (by weight) of thallium.
- Around 70% of the total thallium is used in the electronics industries.
- Thallium is stored in mineral oil because of its reactivity.
Properties of thallium
Here is a list of some physical properties and chemical properties of thallium.
Physical properties of thallium
- Thallium has a silvery gray appearance.
- Thallium is soft metal and it can be cut with a knife too.
- The density of thallium is 11.85 g/cm3 and its atomic mass is 204.38 amu.
- The melting point and boiling point of thallium is 577 K and 1746 K respectively.
- Thallium has HCP crystal structure.
- Thallium has many isotopes, and the most abundant isotope is 205Tl.
Chemical properties of thallium
- Thallium easily reacts with the atmospheric oxygen and tarnishes, if kept open in the air.
- Thallium reacts with water and forms a thallium hydroxide.
- Thallium has an electronegativity of 1.62 on the pauling scale.
Uses of thallium
Here are some uses of the thallium element.
- Thallium oxide is used in making glasses that require a higher refractive index.
- Thallium is also used in electronic industries (specially in the semiconductor material used for selenium rectifiers).
- Thallium sulfide is a compound of thallium which is used in photocells.
- Thallium – Element information, properties and uses | Periodic Table. (n.d.). Thallium – Element Information, Properties and Uses | Periodic Table. https://www.rsc.org/periodic-table/element/81/thallium
- Bedford, et al. (1996, April 1). Recommended values of temperature on the International Temperature Scale of 1990 for a selected set of secondary reference points. Metrologia, 33(2), 133–154. https://doi.org/10.1088/0026-1394/33/2/3
- Allred, A. (1961, June). Electronegativity values from thermochemical data. Journal of Inorganic and Nuclear Chemistry, 17(3–4), 215–221. https://doi.org/10.1016/0022-1902(61)80142-5
- Thallium – Wikipedia. (2008, February 2). Thallium – Wikipedia. https://en.wikipedia.org/wiki/Thallium
- P. (n.d.). Thallium | Tl (Element) – PubChem. Thallium | Tl (Element) – PubChem. https://pubchem.ncbi.nlm.nih.gov/element/Thallium
- It’s Elemental – The Element Thallium. (n.d.). It’s Elemental – the Element Thallium. https://education.jlab.org/itselemental/ele081.html
- Thallium Statistics and Information | U.S. Geological Survey. (n.d.). Thallium Statistics and Information | U.S. Geological Survey. https://www.usgs.gov/centers/national-minerals-information-center/thallium-statistics-and-information
- C&EN: IT’S ELEMENTAL: THE PERIODIC TABLE – THALLIUM. (n.d.). C&EN: IT’S ELEMENTAL: THE PERIODIC TABLE – THALLIUM. https://pubsapp.acs.org/cen/80th/print/thalliumprint.html?
- Periodic Table of Elements: Los Alamos National Laboratory. (n.d.). Periodic Table of Elements: Los Alamos National Laboratory. https://periodic.lanl.gov/81.shtml
- Atomic Weight of Thallium | Commission on Isotopic Abundances and Atomic Weights. (n.d.). Atomic Weight of Thallium | Commission on Isotopic Abundances and Atomic Weights. https://ciaaw.org/thallium.htm
- Atomic Data for Thallium (Tl). (n.d.). Atomic Data for Thallium (Tl). https://physics.nist.gov/PhysRefData/Handbook/Tables/thalliumtable1.htm
- Possolo, et al. (2018, January 4). Interpreting and propagating the uncertainty of the standard atomic weights (IUPAC Technical Report). Pure and Applied Chemistry, 90(2), 395–424. https://doi.org/10.1515/pac-2016-0402
- Emsley, J. (2011). Nature’s Building Blocks: An A-Z Guide to the Elements. United Kingdom: OUP Oxford.
- Haynes, W. M. (Ed.). (2014, June 4). CRC Handbook of Chemistry and Physics. https://doi.org/10.1201/b17118
- Electronic structure of the elements. (2000, March). The European Physical Journal C, 15(1–4), 78–79. https://doi.org/10.1007/bf02683401
- James A. M. & Lord M. P. (1992). Macmillan’s chemical and physical data. Macmillan.
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