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. Our bodies contain about 14 milligrams, and every cell in a human body contains more than a million selenium atoms. Diagram of the nuclear composition and electron configuration of an atom of selenium-80 (atomic number: 34), the most common isotope of this element. Medium = substitution is possible but there may be an economic and/or performance impact Sources, facts, uses, scarcity (SRI), podcasts, alchemical symbols, videos and images. Selenium (selenium atoms only) has several different forms. Atomic Weight: 78.971. Similar Illustrations See All. Where more than one isotope exists, the value given is the abundance weighted average. Sign with atomic number and atomic weight. 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. The element occurs in copper ores and rare minerals … CAS number 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. Areas covered include atomic structure, physical properties, atomic interaction, thermodynamics, identification, atomic size, crystal structure, history, abundances, and nomenclature. The percentage of a commodity which is recycled. A group or a family is each column on the periodic table. It is therefore useful in photocells, solar cells and photocopiers. 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 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. The mass of an atom relative to that of carbon-12. The nucleus consists of 34 protons (red) and 45 neutrons (orange). Selenium, isotope of mass 75. Bond enthalpy (kJ mol−1)A measure of how much energy is needed to break all of the bonds of the same type in one mole of gaseous molecules. It shows similar properties as sulfur, tellurium, and arsenic. Selenium (Se). The selenium atom has a radius of 120 pm and a Van der Waals radius of 190 pm. 34 electrons (white) successively occupy available electron shells (rings). In fact a little investigation showed me that it was perfectly safe in small amounts. Group Number: 16. Selenium (atomic number 32, symbol Se) is a nonmetal and a chemical element that is added to dietary supplements and is an essential mineral. Atomic Number of Selenium is 34. Allotropes It is given by the ratio of the pressure on a body to the fractional decrease in volume. Chemical symbol for Selenium is Se. The element symbol of selenium is Se. 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 most common ore of selenium are the sulfide ores. You do not have JavaScript enabled. Selenium's Melting Point is 429.5F. We know selenium is there, right under sulfur, in the periodic table, but it doesn't get much attention. It was first observed by the Swedish scientist Jons Jacob Berzelius. 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. Melting point of Selenium is 217 °C and its the boiling point is 685 °C. 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. element symbol for selenium stock illustrations A measure of how difficult it is to deform a material. The temperature at which the liquid–gas phase change occurs. But it's not all bad news. The number of atoms of the element per 1 million atoms of the Earth’s crust. Atomic Mass of Selenium Selenium is not commonly found in its free or elemental form. 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. Sign with atomic number and atomic weight. Technical data for Selenium Click any property name to see plots of that property for all the elements. This is where the artist explains his interpretation of the element and the science behind the picture. Relative atomic mass It has the atomic number 34 in the periodic table. 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. 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. Half of the distance between two unbonded atoms of the same element when the electrostatic forces are balanced. Selenium Sign with atomic number. Selenium : Atomic Number 34 , Mass Number 78 . Atomic weight of Selenium is 78.971 u or g/mol. It is defined as being the charge that an atom would have if all bonds were ionic. Density is the mass of a substance that would fill 1 cm3 at room temperature. While some of the allotropic forms of selenium resemble those that we know well from study of sulphur, there are others that are different. Period Number: 4. Members of the oxygen family become more active as you move upward on the periodic table. Selenium has both a photovoltaic action (converts light to electricity) and a photoconductive action (electrical resistance decreases with increased illumination). Each allotrope has different physical properties. Values are given for typical oxidation number and coordination. 2020-12-26. The melting point of selenium is 494 degrees Kelvin or 221.85 degrees Celsius or degrees Celsius. So much for trying to do a "wikipedia" search for this "hidden" element! In mineral form, selenium is present in the form of selenite or selenide compounds. Properties Physical properties. He also noted that it was like sulfur and indeed had properties intermediate between sulfur and tellurium. Atomic Number-34 Atomic Mass-78.96 Group Number-16 Selenium's group number 16, is called the chalcogens, or the oxygen family. 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. Group Name: Chalcogen. Where more than one isotope exists, the value given is the abundance weighted average. Symbol of the selenium element is Se. Too little selenium can cause health problems, but too much is also dangerous. But we require it as part of various enzymes, such as glutathione peroxidase, as well as in the thyroid. Selenium burns in air and is toxic by inhalation or ingestion. This is calculated by combining the scores for crustal abundance, reserve distribution, production concentration, substitutability, recycling rate and political stability scores. 34 Se Selenium 78.971. Selenium, symbol Se, has a Simple Monoclinic structure and Gray color. Selenium in its pure form can not be found on the surface of our planet, but it exists in some rare minerals and special muds. Elements are organised into blocks by the orbital type in which the outer electrons are found. The role of the element in humans, animals and plants. Selenium is a chemical element with atomic number 34 and symbol Se. The group name of that belongs to Selenium is Chalcogen. Uncombined elements have an oxidation state of 0. But the diversity of uses of selenium does not stop with shampoo and horse food supplements and photovoltaics. Ok so I'll take you through some interesting facts and data about Selenium (That most people don't know). The temperature at which the liquid–gas phase change occurs. Selenium is a chemical element with symbol Se and atomic number 34. Selenium (Se). Covalent radiusHalf of the distance between two atoms within a single covalent bond. Images © Murray Robertson 1999-2011 Polonium is a chemical element with atomic number 84 which means there are 84 protons in its nucleus.Total number of protons in the nucleus is called the atomic number of the atom and is given the symbol Z.The total electrical charge of the nucleus is therefore +Ze, where e (elementary charge) equals to 1,602 x 10-19 coulombs. The atomic number of each element increases by one, reading from left to right. CPT0VS6XYI. The RSC has been granted the sole and exclusive right and licence to produce, publish and further license the Images. Melting point 494K. Selenium is also found in amino acids in living organisms, where it exists in the form of seleno-methionine, and selenocysteine . Density (g cm−3) But what is an "Atomic Number"? Electron affinityThe energy released when an electron is added to the neutral atom and a negative ion is formed. The transition of a substance directly from the solid to the gas phase without passing through a liquid phase. In no event shall the RSC be liable for any damages including, without limitation, indirect or consequential damages, or any damages whatsoever arising from use or loss of use, data or profits, whether in action of contract, negligence or other tortious action, arising out of or in connection with the use of the material available from this Site. Some elements exist in several different structural forms, called allotropes. It has isotopic forms with a varying number of neutrons, but the protons is always the same (the atomic number 34). https://www.nuclear-power.net/Selenium-atomic-number-mass-density Copyright of and ownership in the Images reside with Murray Robertson. 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. 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. Selenium boiling point is 685 °C. Boiling point: 1,265 F (685 C) 8. Data for this section been provided by the British Geological Survey. Block Number of protons in Selenium is 34. Atoms of the same element with different numbers of neutrons. In the human body, selenium content ranges betwe… A measure of how difficult it is to compress a substance. A horizontal row in the periodic table. The number of protons in an atom. The oxidation state of an atom is a measure of the degree of oxidation of an atom. This chemical element can be found in two forms: a red color powder or light grey color metal. The temperature at which the solid–liquid phase change occurs. 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. Selenium (Se) is a grey non metal that can also exist as a red allotrope. Selenium trioxide (SeO 3) Interesting facts: It is similar to sulfur in its form and compounds. Its chemical symbol is Se and its atomic number is 34. Our selenium page has over 260 facts that span 106 different quantities. The arrangements of electrons above the last (closed shell) noble gas. The colour ranges from grey metallic to red glassy. A vertical column in the periodic table. Selenium is a chemical element. These values were determined using several different methods. Low = substitution is possible with little or no economic and/or performance impact. A vertical column in the periodic table. These values were determined using several different methods. Selenium is a chemical element with symbol Se and atomic number 34. Also intriguing to me was a recent study indicating that selenium deficient soils may play a role in susceptibility to HIV/AIDS in Africa. 4 Related Records Expand this section. 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. Selenium chemical element. Atomic number We hope that you enjoy your visit to this Site. Selenium exhibits photovoltaic action, where light is converted directly into electricity, and photoconductive … Data for this section been provided by the. This Site has been carefully prepared for your visit, and we ask you to honour and agree to the following terms and conditions when using this Site. It can also convert AC electricity to DC electricity, so is extensively used in rectifiers. Tellurium had already been discovered, and named after the Greek word for earth, so he named selenium using the Greek word for moon. 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. It decreases electrical resistance with increased illumination. 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. Connected lines with dots. These muds are either roasted with sodium carbonate or sulfuric acid, or smelted with sodium carbonate to release the selenium. Boiling point of Selenium in Kelvin is 958 K. Selenium melting point is 217 °C. Selenium is not an abundant element. 400 micrograms per day is set as the safe upper intake level in humans. Half of the distance between two unbonded atoms of the same element when the electrostatic forces are balanced. Le sélénium est un oligoélément et un bioélément, mais à très faible dose. Phase at room temperature: Solid 6. Selenium (atomic symbol: Se, atomic number: 34) is a Block P, Group 16, Period 4 element with an atomic radius of 78.96. The biggest use of selenium is as an additive to glass. Melting point of Selenium is 217 °C and its the boiling point is 685 °C. Contents . That was Cambridge University's Bernie Bulkin with the story of Selenium. 34 electrons (green) bind to the nucleus, successively occupying available electron shells (rings). History and Discovery . Yum! Selenium Element: Selenium is the chemical in the 16th group and 4th period of the periodic table.