Molecule And Communication Background. Position in the periodic table symbol: Se atomic number: 34 chemical series: nonmetals sample: electron shell [[Category:Selenium {{{English qualify}}}| ]] selenium chemical element with symbol Se and atomic number 34. Yum! Atomic Number-34 Atomic Mass-78.96 Group Number-16 Selenium's group number 16, is called the chalcogens, or the oxygen family. When I was in my early 20s I developed a dry scalp condition for a few years, probably a result of anxiety over research grants I was trying to obtain. Some elements exist in several different structural forms, called allotropes. State of Selenium is Solid at standard temperature and pressure Selenium in its allotropic red form is added to glass to give it a scarlet color, but it also can be used to remove the greenish tint sometimes found in glass due to iron compounds. Sign with atomic number and atomic weight. The availability of suitable substitutes for a given commodity. Selenium is a chemical element with symbol Se and atomic number 34. The chemical symbol for Selenium is Se. Selenium is a other nonmetal element. It is found in several forms, but is usually prepared with a crystalline structure. Selenium chemical element. Allotropes While selenium is not a metallic element, gray selenium is a good photoconductor, and was used in early photocells. Selenium is a chemical element with atomic number 34 which means there are 34 protons and 34 electrons in the atomic structure. Selenium is added to synthetic rubber to improve resistance to abrasion, it has been added to brass, along with bismuth, to replace lead in pipes, and it is used, as sodium selenate, as an insecticide to stop attacks on flowering plants such as chrysanthemums and carnations. Where the element is most commonly found in nature, and how it is sourced commercially. Atomic weight of Selenium is 78.971 u or g/mol. Molecule And Communication Background. Selenium Overview . We hope that you enjoy your visit to this Site. High = substitution not possible or very difficult. There have been numerous studies, none of them very conclusive, about the possible role of selenium in cancer prevention, and in increasing the efficacy of chemotherapy. Save Comp. Krypton has been portrayed consistently as having been destroyed just after Superman's flight from the planet, with exact details of its destruction varying by time period, writers and franchise. In fact a little investigation showed me that it was perfectly safe in small amounts. The arrangements of electrons above the last (closed shell) noble gas. But for horses, with their more limited diet, selenium deficiency is common and often corrected with dietary supplements. Element Classification: Non-metal. Period It converts light into electricity. 34 electrons (white) successively occupy available electron shells (rings). Each allotrope has different physical properties. The origin of the name comes from the Greek word selene meaning moon. Selenium is an essential trace element for some species, including humans. The melting point of selenium is 494 degrees Kelvin or 221.85 degrees Celsius or degrees Celsius. What's in a name? But what is an "Atomic Number"? it exists in the form of ores and minerals. The inorganic chemistry textbooks that I studied from talk extensively about sulphur and, where appropriate, say things like 'selenium also forms similar acids', or 'selenium also has many allotropic forms'. Know what is Selenium, Chemical Properties of Selenium, Atomic Mass, and more at BYJU'S Selenium symbol. 1 Structures Expand this section. Diagram of the nuclear composition and electron configuration of an atom of selenium-80 (atomic number: 34), the most common isotope of this element. Selenium is a chemical element with symbol Se and atomic number 34. Selenium definition, a nonmetallic element chemically resembling sulfur and tellurium, occurring in several allotropic forms, as crystalline and amorphous, and having an electrical resistance that varies under the influence of light. Selenium chemical element. A measure of how difficult it is to deform a material. History and Discovery . The element occurs in copper ores and rare minerals … At one time virtually all copying machines used selenium ; this has now been largely replaced by organic photoconductors. Un préfixe (Nouveau mot formé en ajoutant une ou plusieurs lettres devant le mot.) A Melting Point is the temperature at which a substance melts. Selenium (Se) Atomic Data for Selenium (Se) Atomic Number = 34 Atomic Weight = 78.96 … Indeed, the newest and most promising class of mass produced solar cells are copper indium gallium selenide. Contents . The percentage of the world reserves located in the country with the largest reserves. It has 34 protons and 34 electrons and a mass number of 78.96. Selenium was discovered jointly in 1817 by Swedish chemists Jöns Jakob Berzelius (1779–1848) and Johan Gottlieb Gahn (1745–1818). Selenium – Atomic Mass – Atomic Weight – Se 2020-11-21 by Nick Connor Atomic Mass of Selenium Atomic mass of Selenium is 78.96 u. It is defined as the equilibrium pressure exerted by the gas produced above a substance in a closed system. The selenium atom has a radius of 120 pm and a Van der Waals radius of 190 pm. The treatment for this was a shampoo containing selenium sulphide, surprising to me because I thought that selenium was highly toxic. It shows similar properties as sulfur, tellurium, and arsenic. The nucleus consists of 34 protons (red) and 45 neutrons (orange). Atomic symbol (on the Periodic Table of Elements): Se 3. Each allotrope has different physical properties. It can also convert AC electricity to DC electricity, so is extensively used in rectifiers. The selenium atom has a radius of 120 pm and a Van der Waals radius of 190 pm. The number of atoms of the element per 1 million atoms of the Earth’s crust. Name: Selenium Symbol: Se Atomic Number: 34 Atomic Mass: 78.96 amu Melting Point: 217.0 °C (490.15 K, 422.6 °F) Boiling Point: 684.9 °C (958.05005 K, 1264.8201 °F) Number of Protons/Electrons: 34 Number of Neutrons: 45 Classification: Non-metal Crystal Structure: Hexagonal Density @ 293 K: 4.79 g/cm 3 Color: gray Atomic Structure The number of electrons in each of Selenium's shells is 2, 8, 18, 6 and its electron configuration is [Ar] 3d 10 4s 2 4p 4. This is a list of the 118 chemical elements which have been identified as of 2021. A higher recycling rate may reduce risk to supply. Selenium is a chemical element with atomic number 34 and symbol Se. Properties: Selenium has an atomic radius of 117 pm, a melting point of 220.5°C, boiling point of 685°C, with oxidation states of 6, 4, and -2. We welcome your feedback. Electron configuration The availability of suitable substitutes for a given commodity. Phase at Room Temperature: Solid. A measure of how difficult it is to compress a substance. Element 34 of Periodic table is Selenium with atomic number 34, atomic weight 78.96. The images may not be posted on any website, shared in any disc library, image storage mechanism, network system or similar arrangement. Density: 4.809 grams per cubic centimeter 5. 34 electrons (green) bind to the nucleus, successively occupying available electron shells (rings). Group Number: 16. At first he thought it was the element tellurium because it gave off a strong smell of radishes when heated, but he eventually realised that it was in fact a new element. The atomic number of each element increases by one, reading from left to right. Each entry has a full citation identifying its source. Selenium was discovered by Jöns Jacob Berzelius at Stockholm in 1817. The Atomic number, Atomic mass and the number of valance electrons all increase from left to right. Sublimation Our selenium page has over 260 facts that span 106 different quantities. Both sulfur and arsenic have some healing properties, and since neighbors in the periodic table have similar properties, it is not surprising that selenium seems to influence human health. Also intriguing to me was a recent study indicating that selenium deficient soils may play a role in susceptibility to HIV/AIDS in Africa. Connected lines with dots. Chemistry in its element is brought to you by the Royal Society of Chemistry and produced by. Atomic Weight: 78.971. 96 @inproceedings{WinSeleniumA, title={Selenium : Atomic Number 34 , Mass Number 78 . Its chemical symbol is Se and its atomic number is 34. The atomic number of selenium is 34. 3 Chemical and Physical Properties Expand this section. Selenium (atomic symbol: Se, atomic number: 34) is a Block P, Group 16, Period 4 element with an atomic radius of 78.96. Diagram of the nuclear composition and electron configuration of an atom of selenium-80 (atomic number: 34), the most common isotope of this element. Half of the distance between two unbonded atoms of the same element when the electrostatic forces are balanced. But I save the best occurrence of selenium in nature for last. Density is the mass of a substance that would fill 1 cm. The Chemical Abstracts Service registry number is a unique identifier of a particular chemical, designed to prevent confusion arising from different languages and naming systems. Selenium is a chemical element with atomic number 34 and symbol Se. You may not further copy, alter, distribute or otherwise use any of the materials from this Site without the advance, written consent of the RSC. The number of electrons in each of Selenium's shells is 2, 8, 18, 6 and its electron configuration is [Ar] 3d 10 4s 2 4p 4. Subsequently, selenium and various selenium compounds have been used in a variety of photoconductor and photovoltaic applications. These values were determined using several different methods. Selenium is an element 34 protons and 46 neutrons. Selenium has atomic number 34, meaning each atom has 34 protons. While some of the allotropic forms of selenium resemble those that we know well from study of sulphur, there are others that are different. Selenium is one of those all too common elements that is essential to life in small quantities, and very toxic in larger quantities. Political stability of top reserve holder. Se is a non-metal. It can be also added as catalyst and as electricity convertor in rectifiers. It has the atomic number 34 in the periodic table. — In-game description Selenium is a Raw Material introduced in v2.0. Atomic weight (average mass of the atom): 78.96 4. Our bodies contain about 14 milligrams, and every cell in a human body contains more than a million selenium atoms. Number of protons in Selenium is 34. Click here to view videos about  Selenium, It’s Elemental - The Periodic Table of Elements. Symbol: Se; atomic weight: 78.96; atomic number: 34; specific gravity: (gray) 4.80 at 25°C, (red) 4.50 at 25°C. These blocks are named for the characteristic spectra they produce: sharp (s), principal (p), diffuse (d), and fundamental (f). Selenium is also used as an additive to make stainless steel. Selenium is a chemical element which is placed in the 16th group and 4th period in the periodic table. Our selenium page has over 260 facts that span 106 different quantities. Most of the world’s selenium is obtained from the anode muds produced during the electrolytic refining of copper. Once you have smelled it you will never forget it, nor underestimate the impact that this interesting element can have. Selenium is a chemical element. https://www.nuclear-power.net/Selenium-atomic-number-mass-density Atomic Number – Protons, Electrons and Neutrons in Polonium. Areas covered include atomic structure, physical properties, atomic interaction, thermodynamics, identification, atomic size, crystal structure, history, abundances, and nomenclature. The element symbol of selenium is Se. Atomic Number: 34. Krypton is a fictional planet in the DC Comics universe, and the native world of the super-heroes Superman, Supergirl, and Krypto the "super dog". A vertical column in the periodic table. Selenium is used to make pigments for ceramics, paint and plastics. Members of the oxygen family become more active as you move upward on the periodic table. Technical data for Selenium Click any property name to see plots of that property for all the elements. The selenium atom has a radius of 120 pm and a Van der Waals radius of 190 pm. Each entry has a full citation identifying its source. Selenium is considered to be a nonmetal. Know what is Selenium, Chemical Properties of Selenium, Atomic Mass, and more at BYJU'S Se is a non-metal. Selenium is not an abundant element. Know everything about Selenium Facts, Physical Properties, Chemical Properties, Electronic configuration, Atomic and Crystal Structure. Most important, so called gray selenium consists of long chains of atoms forming extended helical structures. The origin of the name comes from the Greek word selene meaning moon. Isotopes of an element are atoms that have the same atomic numbers but a different number of neutrons (different mass numbers) in their nuclei. Chemical element of periodic table. In mineral form, selenium is present in the form of selenite or selenide compounds. Atomic Mass of Selenium It has 34 protons and 34 electrons and a mass number of 78.96. Selenium Se chemical element. UNII-CPT0VS6XYI. Classified as a nonmetal, Selenium is a solid at room temperature. Uses of selenium . 400 micrograms per day is set as the safe upper intake level in humans. You may browse, download or print out one copy of the material displayed on the Site for your personal, non-commercial, non-public use, but you must retain all copyright and other proprietary notices contained on the materials. Selenium (atomic number 32, symbol Se) is a nonmetal and a chemical element that is added to dietary supplements and is an essential mineral. Electron affinityThe energy released when an electron is added to the neutral atom and a negative ion is formed. Data for this section been provided by the British Geological Survey. The total electrical charge of the nucleus is therefore +Ze, where e (elementary charge) equals to 1,602 x 10-19 coulombs. Atoms of the same element with different numbers of neutrons. The temperature at which the solid–liquid phase change occurs. Every atom has an atomic number, even Selenium. Atoms of the same element with different numbers of neutrons. The nucleus consists of 34 protons (red) and 46 neutrons (blue). Selenium (atomic symbol: Se, atomic number: 34) is a Block P, Group 16, Period 4 element with an atomic radius of 78.96. Selenium with Atomic Number Z = 34 and Mass Number A = 78.96 is in group VIA and period 4 of the periodic table of the elements.# It has sulfur on top and arsenic next to it. Similar Illustrations See All. Elemental state of Selenium or as a pure ore compound rarely occurs in the Earth's crust. The name is derived from 'selene', the Greek name for the Moon. Nor shall the RSC be in any event liable for any damage to your computer equipment or software which may occur on account of your access to or use of the Site, or your downloading of materials, data, text, software, or images from the Site, whether caused by a virus, bug or otherwise. A horizontal row in the periodic table. Most of these seem to indicate that if it is effective at all, it works somehow in conjunction with vitamin E, which, like selenium, plays an antioxidant role in the body. Selenium is known to have over 20 different isotopes; however, only 5 of them are stable. Selenium exhibits photovoltaic action, where light is converted directly into electricity, and photoconductive … atom atomic atomic␣number atomicus chemical chemical␣element Chemie element elemento elemento␣químico Elementum nonmetallic number numerus Química químico scheikunde seleen Selen Selenio selênio selenium symbol this with. Pornographic, defamatory, libellous, scandalous, fraudulent, immoral, infringing or otherwise unlawful use of the Images is, of course, prohibited. Element Selenium (Se), Group 16, Atomic Number 34, p-block, Mass 78.971. The five stable isotopes of selenium are 2020-12-26. Selenium has a beautiful name coming after the Greek name for the Moon. Periodic Table of the. The mass of an atom relative to that of carbon-12. The number of electrons in each of Selenium's shells is 2, 8, 18, 6 and its electron configuration is [Ar] 3d 10 4s 2 4p 4. But the diversity of uses of selenium does not stop with shampoo and horse food supplements and photovoltaics. The number of electrons in each of Selenium's shells is 2, 8, 18, 6 and its electron configuration is [Ar] 3d 10 4s 2 4p 4. Ok so I'll take you through some interesting facts and data about Selenium (That most people don't know). In the human body, selenium content ranges betwe… Symbol of the selenium element is Se. The most common ore of selenium are the sulfide ores. The atom consist of a small but massive nucleus surrounded by a cloud of rapidly moving electrons. In such cases we would ask you to sign a Visual Elements licence agreement, tailored to the specific use you propose. This is where the artist explains his interpretation of the element and the science behind the picture. All such documents and related graphics are provided "as is" without any representation or endorsement made and warranty of any kind, whether expressed or implied, including but not limited to the implied warranties of fitness for a particular purpose, non-infringement, compatibility, security and accuracy. Melting point Selenium (atomic symbol: Se, atomic number: 34) is a Block P, Group 16, Period 4 element with an atomic radius of 78.96. The chemical symbol for Selenium is Se. The mass of an atom relative to that of carbon-12. Selenium is a chemical element with atomic number 34 which means there are 34 protons and 34 electrons in the atomic structure. First ionisation energyThe minimum energy required to remove an electron from a neutral atom in its ground state. Specific heat capacity is the amount of energy needed to change the temperature of a kilogram of a substance by 1 K. A measure of the stiffness of a substance. It is defined as being the charge that an atom would have if all bonds were ionic. Melting point: 429 degrees Fahrenheit (220.5 degrees Celsius) 7. Half of the distance between two atoms within a single covalent bond. Melting point of Selenium in Kelvin is 453 K. Abundant value of Selenium is 0.05 mg/kg. You're listening to Chemistry in its element brought to you by. Hello, this week flaky scalps, skunks, dead polo ponies and an element that makes you stink of garlic. Melting point of Selenium is 217 °C and its the boiling point is 685 °C. Some selenium compounds decolourise glass, while others give a deep red colour. Selenium Sign with atomic number. Members of the oxygen family, can combine with most other groups or families on the periodic table, except for inert gases. element symbol for selenium stock illustrations Where more than one isotope exists, the value given is the abundance weighted average. Berzelius found that selenium was present in samples of tellurium and gave that element its characteristic smell. We know selenium is there, right under sulfur, in the periodic table, but it doesn't get much attention. Atomic Number of Selenium Selenium is a chemical element with atomic number 34 which means there are 34 protons and 34 electrons in the atomic structure. Murray Robertson is the artist behind the images which make up Visual Elements. It provides a measure of how difficult it is to extend a material, with a value given by the ratio of tensile strength to tensile strain. Atomic radius, non-bonded The atomic number of each element increases by one, reading from left to right. Melting Point- 429.5 F Boiling Point- 1,265 F: What is a Melting Point? The RSC makes no representations whatsoever about the suitability of the information contained in the documents and related graphics published on this Site for any purpose. Welcome to "A Visual Interpretation of The Table of Elements", the most striking version of the periodic table on the web. Number of protons in Selenium is 34. The nucleus consists of 34 protons (red) and 46 neutrons (blue). The rationale is that low selenium levels are associated with weakened immune systems, since with lack of antioxidant capacity there is stress on the immune system. Sign with atomic number and atomic weight. An integrated supply risk index from 1 (very low risk) to 10 (very high risk). Atomic Number: 34: Atomic Mass: 78.96 atomic mass units Number of Protons: 34: Number of Neutrons: 45: Number of Electrons: 34: Melting Point: 217.0° C: Boiling Point : 684.9° C: Density: 4.79 grams per cubic centimeter: Normal Phase: Solid: Family: Nonmetals: Period: 4: Costs: $300 per pound . Il est toxique (voire très toxique sous certaines formes) à des concentrations à peine plus élevées que celles qui en font un oligoélément indispensable à la diète animale. Illustration about molecule, concept - 151780509 This chemical element can be found in two forms: a red color powder or light grey color metal. He had shares in a sulfuric acid works and he was intrigued by a red-brown sediment which collected at the bottom of the chambers in which the acid was made. Selenium Element: Selenium is the chemical in the 16th group and 4th period of the periodic table. It is toxic in high amount but is an essential micronutrient for all living things. Atomic Number of Selenium Selenium is a chemical element with atomic number 34 which means there are 34 protons and 34 electrons in the atomic structure. Molecule And Communication Background. Selenium is a metalloid with atomic number 34 (discovered in 1817 by J. J. Berzelius) that has been demonstrated to be essential for living organisms. Number … Melting point 494K. It is indicated by the symbol Se and the atomic number of selenium is 34. at 0℃ and one atmosphere pressure. Atomic weight of Selenium is 78.971 u or g/mol. Low = substitution is possible with little or no economic and/or performance impact. A measure of the propensity of a substance to evaporate. 5 Chemical Vendors. Selenium element symbol isolated on white background; Selenium chemical element. Elements are organised into blocks by the orbital type in which the outer electrons are found. The biggest use of selenium is as an additive to glass. The Chemical Abstracts Service registry number is a unique identifier of a particular chemical, designed to prevent confusion arising from different languages and naming systems. Illustration about electron, mendeleev - 151780818 Le sélénium est un oligoélément et un bioélément, mais à très faible dose. Chemical element of periodic table. Values are given for typical oxidation number and coordination. I'm Chris Smith, thank you for listening and goodbye. He also noted that it was like sulfur and indeed had properties intermediate between sulfur and tellurium. The element is named after Selene, the Greek goddess of the moon. Sources, facts, uses, scarcity (SRI), podcasts, alchemical symbols, videos and images. Atomic number 34, Dioxyde de Sélénium, Ebselen, L-Selenomethionine, L-Sélénométhionine, Levure Sélénisée, Numéro Atomique 34, Se, Selenio, Selenite, Sélénite de Sodium, Sélénium, Selenium Ascorbate, Selenium Dioxide, Selenized Yeast, Selenomethionine, Sélénométhionine, Sodium Selenite. Boiling point And you can catch the facts about Krypton, rather than the fiction with Angleos Michaelides at next week's Chemistry in its Element. Boiling point: 1,265 F (685 C) 8. The group name of that belongs to Selenium is Chalcogen. Collected on planet surfaces and from asteroids.Selenium, Se, atomic number 34. Selenium (atomic number 32, symbol Se) is a nonmetal and a chemical element that is added to dietary supplements and is an essential mineral. Here are the properties of selenium, according to the Jefferson Lab: 1. More... Molecular Weight: 74.922523 g/mol. The RSC maintains this Site for your information, education, communication, and personal entertainment. The most important use of this chemical element is in glass production. Selenium (Se) is a grey non metal that can also exist as a red allotrope. The higher the value, the larger risk there is to supply. – kaufen Sie diese Vektorgrafik und finden Sie ähnliche Vektorgrafiken auf Adobe Stock CPT0VS6XYI. hydrure␣de␣sélénium The atomic number of a chemical element is the number of protons found in the nucleus of the atom of that element. This is approximately the sum of the number of protons and neutrons in the nucleus. Sign Selenium with atomic number and atomic weight. Sources, facts, uses, scarcity (SRI), podcasts, alchemical symbols, videos and images. Areas covered include atomic structure, physical properties, atomic interaction, thermodynamics, identification, atomic size, crystal structure, history, abundances, and nomenclature. Selenium is a chemical element with atomic number 34 which means there are 34 protons in its nucleus. Chemical symbol for Selenium is Se. Group It is a nonmetal element with the atomic number 34. For a wider selection of images connected with Selenium, see Category:Selenium. Name: Selenium Symbol: Se Atomic Number: 34 Atomic Mass: 78.96 amu Melting Point: 217.0 °C (490.15 K, 422.6 °F) Boiling Point: 684.9 °C (958.05005 K, 1264.8201 °F) Number of Protons/Electrons: 34 Number of Neutrons: 45 Classification: Non-metal Crystal Structure: Hexagonal Density @ 293 K: 4.79 g/cm 3 Color: gray Atomic Structure Members of a group typically have similar properties and electron configurations in their outer shell. It was Berzelius who discovered selenium in 1817, as an impurity in sulphuric acid. Atomic Number Selenium. Covalent radiusHalf of the distance between two atoms within a single covalent bond. Create . Medium = substitution is possible but there may be an economic and/or performance impact, Low = substitution is possible with little or no economic and/or performance impact, If you wish to use the Images in a manner not permitted by these terms and conditions please contact the Publishing Services Department. Chemical element of periodic table. It readily forms hard, stable carbides in alloys, and for this reason most of world production of the element (about 80%) is used in steel alloys, including high-strength alloys and superalloys. The selenium atom has a radius of 120 pm and a Van der Waals radius of 190 pm. Half of the distance between two unbonded atoms of the same element when the electrostatic forces are balanced. Atomic Number of Selenium is 34. Chemical symbol for Selenium is Se. Density (g cm−3) Relative atomic mass Total number of protons in the nucleus is called the atomic number of the atom and is given the symbol Z. Medium = substitution is possible but there may be an economic and/or performance impact That was Cambridge University's Bernie Bulkin with the story of Selenium. Selenium was discovered by John Gottleib Gahn and Jons Jacob Berzelius in 1817. Atomic Symbol. Selenium is an element of group VIA and period 4 of the periodic table with Atomic Number Z=34 and Mass Number A=78.96 [1]. The tendency of an atom to attract electrons towards itself, expressed on a relative scale. Chemical 34 element of periodic table. If you wish to use the Images in a manner not permitted by these terms and conditions please contact the Publishing Services Department by email. A group or a family is each column on the periodic table. The temperature at which the liquid–gas phase change occurs. Selenium is in period 4 on the periodic table. 96}, author={D. T. Win} } D. T. Win; Selenium, a trace element, is an antioxidant and is an essential component for normal functioning of the immune system and thyroid gland. Copyright of and ownership in the Images reside with Murray Robertson. Diagram of the nuclear composition, electron configuration, chemical data, and valence orbitals of an atom of selenium-79 (atomic number: 34), an isotope of this element. Elements are organised into blocks by the orbital type in which the outer electrons are found. The percentage of an element produced in the top producing country. Images © Murray Robertson 1999-2011 Classified as a nonmetal, Selenium is a solid at room temperature. So it can clear up an itchy scalp but it might make you stink in the process. Selenium boiling point is 685 °C. High amount of selenium is also present in oceans . If you are in any doubt, please ask. He also became affected by it personally – it can be absorbed through the skin – and it caused him to experience the bad breath associated with those who work with this element. Selenium has both a photovoltaic action (converts light to electricity) and a photoconductive action (electrical resistance decreases with increased illumination). Selenium (selenium atoms only) has several different forms. Selenium (Se). Group Name: Chalcogen. CAS number Data for this section been provided by the. It can convert AC electricity to DC electricity. Selenium (atomic symbol: Se, atomic number: 34) is a Block P, Group 16, Period 4 element with an atomic radius of 78.96. Généralité sur l'élément et histoire. But we require it as part of various enzymes, such as glutathione peroxidase, as well as in the thyroid. 2 Names and Identifiers Expand this section. Se Chemical element of the periodic table on a glossy white. Selenium (Se). Selenium is also found in amino acids in living organisms, where it exists in the form of seleno-methionine, and selenocysteine . Selenium is toxic to the scalp fungus that causes dandruff so it is used in some anti-dandruff shampoos. A percentile rank for the political stability of the country with the largest reserves, derived from World Bank governance indicators. It is a micronutrient. It is indicated by the symbol Se and the atomic number of selenium is 34.