Search results
Results From The WOW.Com Content Network
Scandium(III) oxide or scandia is a inorganic compound with formula Sc 2 O 3.It is one of several oxides of rare earth elements with a high melting point.It is used in the preparation of other scandium compounds as well as in high-temperature systems (for its resistance to heat and thermal shock), electronic ceramics, and glass composition (as a helper material).
In all four halides, the scandium is 6-coordinated. They can be prepared by reacting scandium oxide or scandium hydroxide with the corresponding acid: [3] Sc(OH) 3 + 3 HX → ScX 3 + 3 H 2 O. The halides are Lewis acids; for example, ScF 3 dissolves in a solution containing excess fluoride ion to form [ScF 6] 3−. The coordination number 6 is ...
Scandium has been proposed for use in solid oxide fuel cells (SOFCs) as a dopant in the electrolyte material, typically zirconia (ZrO₂). [72] Scandium oxide (Sc₂O₃) is one of several possible additives to enhance the ionic conductivity of the zirconia, improving the overall thermal stability, performance and efficiency of the fuel cell. [73]
This page was last edited on 19 November 2016, at 18:04 (UTC).; Text is available under the Creative Commons Attribution-ShareAlike 4.0 License; additional terms may apply.
Scandium oxide is amphoteric; lutetium oxide is more basic (although it can with difficulty be made to display some acidic properties), and yttrium oxide is more basic still. [58] Salts with strong acids of these metals are soluble, whereas those with weak acids (e.g. fluorides, phosphates, oxalates) are sparingly soluble or insoluble. [53]
Kangite is an exceedingly rare scandium mineral, a natural form of impure scandium oxide (Sc 2 O 3), with the formula (Sc,Ti,Al,Zr,Mg,Ca, ) 2 O 3. It crystallizes in the cubic crystal system diploidal class. [1] In terms of chemistry it scandium-analogue of tistarite. Both kangite and tistarite were discovered in the Allende meteorite. [2] [1 ...
Element Negative states Positive states Group Notes −5 −4 −3 −2 −1 0 +1 +2 +3 +4 +5 +6 +7 +8 +9 Z; 1 hydrogen: H −1 +1: 1 2 helium: He 0 18
Scandium triflate is used as a reagent in organic chemistry as a Lewis acid. [1] Compared to other Lewis acids, this reagent is stable towards water and can often be used in organic reactions as a true catalyst rather than one used in stoichiometric amounts. The compound is prepared by reaction of scandium oxide with trifluoromethanesulfonic acid.