CHEMICAL SUBSTANCE DATASHEET
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CHEMICAL SUBSTANCE IDENTIFICATION |
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Chemical name |
Scandium |
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Synonyms |
scandium, Sc, scandium metal powder, scandium lump, scandium pieces, scandium ingot, scandium foil |
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IUPAC name |
Scandium [1] |
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CAS No |
7440-20-2 [1] |
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REACH registration number |
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EC No |
231-129-2 [1] |
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Molecular formula |
Sc |
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Substance group/chemical family |
metals / transition metal Scandium is a transition metal and it is also considered a rare earth element because it is often found in rare-earth ores. It also shares many of the same chemical properties of other rare-earths. [5, 7] |
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Appearance Physical state Odour Form
Colour |
solid at 20 °C
Scandium is not found free in nature but combined in minute amounts in over 800 minerals. Sc occurs as a principal component in the rare mineral thortveitite, found in Scandinavia and Malagasy [3,7]
Silvery. It develops a slightly yellowish or pinkish cast when oxidized by air. [2] |
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USES AND HANDLING ISSUES |
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Relevant identified uses |
Advanced material composites: Sc F3 a material with negative thermal expansion coefficient. [5] Scandium is used in aluminum-scandium alloys for aerospace industry components and 3D printing as well as in Solid Oxide Fuel Cell (SOFC) applications and for sports equipment such as bicycle frames, fishing rods, golf iron shafts and baseball bats [5] Scandium iodide is used in mercury vapor lamps, which are used to replicate sunlight in studios for the film and television industry. Scandium oxide (scandia) is used to make high intensity “stadium” lights. Sc2O3 and ScVO4 are typical host materials for phosphorus in monitors. [5] The radioactive isotope 45Sc is used in oil refineries as a tracing agent. [5] Very dilute scandium sulfate is used to improve the germination of seeds such as corn, peas and wheat. [5] |
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Handling considerations |
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PHYSICO-CHEMICAL PROPERTIES |
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Molecular weight |
44.96 g/mol [3] |
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Bulk density/Specific gravity |
2.985 g/cm3 [2] |
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pH |
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Particle size |
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EC |
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Melting point |
1541°C [3] |
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Boiling point |
2836°C [3] |
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Flash point |
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Flammability |
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Vapour density |
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Vapour pressure |
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Solubility in water |
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Solubility in organic solvents |
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Solubility in inorganic solvents |
Scandium dissolves slowly in most dilute acids [2] |
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Hydrolysis |
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Ionicity in water |
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Surface tension |
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Dispersion properties |
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Specific surface |
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Stability and reactivity |
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Chemical stability |
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Reactivity hazards |
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Corrosivity |
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Polimerization |
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Incompatibility with various substances |
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Special remarks on reactivity |
Scandium turnings ignite in air with a brilliant yellow flame to form scandium oxide [2,3] It is not attacked by a 1:1 mixture of HNO3 and 48% HF. [2, 3] It reacts with water to form hydrogen gas [3, 5, 6] Scandium reacts with many acids [5] Pure scandium is produced by heating scandium fluoride (ScF3 ) with calcium metal. [6] |
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Physical, chemical and biological coefficient |
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Koc |
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Kow |
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pKa |
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log Kp |
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Henry-constant |
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ENVIRONMENTAL FATE AND BEHAVIOUR |
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Artificial pollution sources |
Scandium is dumped in the environment in many different places, mainly by petrol-producing industries. It can also enter the environment when household equipment is thrown away. Scandium will gradually accumulate in soils and water soils and this will eventually lead to increasing concentrations in humans, animals and soil particles. Sc may cause damage to the cell membranes of water animals, which may influence reproduction and the functions of the nervous system. [6] |
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General terrestrial fate |
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General aquatic fate |
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General atmospheric fate |
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General persistence and degradability |
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Abiotic degradation and metabolites |
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Biodegradation and metabolites |
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Bioconcentration |
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Volatilization |
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Photolysis |
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Hydrolysis |
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Soil adsorption and mobility |
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ENVIRONMENTAL CONCENTRATIONS |
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Measured data |
Scandium is not rare in the Earth’s crust. Estimates vary from 18 to 25 ppm, which is comparable to the abundance of cobalt (20–30 ppm). Scandium is only the 50th most common element on Earth (35th most abundant in the crust), but it is the 23rd most common element in the Sun. However, scandium is distributed sparsely and occurs in trace amounts in many minerals [2, 4] |
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ECOTOXICOLOGICAL INFORMATION |
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General adverse effects on ecosystem |
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Acute toxicity (LC50, EC50) |
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Aquatic systems |
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Terrestrial systems |
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Chronic toxicity (NOEC, LOEC) |
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Aquatic systems |
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Terrestrial systems |
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HUMAN HEALTH EFFECTS and PROTECTION |
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Routes of human exposures |
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General effects |
Scandium is considered to be of low toxicity. [5] |
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Endocrine disruption |
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Mutagenicity |
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Carcinogenicity |
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Reprotoxicity |
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Teratogenicity |
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Skin, eye and respiratory irritations |
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Metabolism: absorption, distribution & excretion |
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Exposure limits |
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Drinking water MAC |
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Other information |
Only trace amounts reach the food chain, so the average person's daily intake is less than 0.1 microgram.[6] Scandium is mostly dangerous in the working environment, due to the fact that damps and gasses can be inhaled with air. This can cause lung embolisms, especially during long-term exposure. Scandium can be a threat to the liver when it accumulates in the human body. [6] |
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Animal toxicity data |
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Acute toxicity (LD50) |
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Chronic toxicity (NOEL, LOEL) |
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ENVIRONMENTAL STANDARDS AND REGULATIONS |
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EINECS regulation |
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OSHA regulations etc. |
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OTHER INFORMATION, SPECIAL REMARKS |
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Classification and proposed labelling with regard to toxicological data |
Danger! According to the classification provided by companies to ECHA in CLP notifications this substance is a flammable solid and is an extremely flammable liquid and vapour. [1] |
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CREATED, LAST UPDATE |
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Created |
2019. 04. 03. |
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Last update |
2019. 04. 04. |
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REFERENCES |
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[1] ECHA, European Chemical Agency, Scandium, https://echa.europa.eu/hu/substance-information/-/substanceinfo/100.028.299, Accessed: 2019.04.03 [2] Wikipedia, Scandium https://en.wikipedia.org/wiki/Scandium, Accessed: 2019.04.03 [3] Periodic Table of Elements, Scandium https://periodic.lanl.gov/21.shtml, Accessed: 2019.04.03 [4] Lide, David R. (2004). CRC Handbook of Chemistry and Physics. Boca Raton: CRC Press. pp. 4–28. ISBN 978-0-8493-0485-9.
[5] "Scandium." Chemicool Periodic Table. Chemicool.com. 18 Oct. 2012.
http://www.chemicool.com/elements/scandium.html Accessed: 2019.04.04
[6] Scandium-Sc, Periodic Table, Lenntech, Water Treatment Solutions https://www.lenntech.com/periodic/elements/sc.htm#ixzz5k7SWoSXG, Accessed: 2019.04.04
[7] Science notes, Scandium Facts https://sciencenotes.org/scandium-facts/ Accessed: 2019.04.04 |
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