Matches in DBpedia 2016-04 for { <http://wikidata.dbpedia.org/resource/Q3733706> ?p ?o }
Showing triples 1 to 42 of
42
with 100 triples per page.
- Q3733706 subject Q8509267.
- Q3733706 abstract "A heteropoly acid is a class of acid made up of a particular combination of hydrogen and oxygen with certain metals and non-metals. This type of acid is a common re-usable acid catalyst in chemical reactions.To qualify as a heteropoly acid, the compound must contain:a metal such as tungsten, molybdenum or vanadium, termed the addenda atom;oxygen;an element generally from the p-block of the periodic table, such as silicon, phosphorus or arsenic, termed the hetero atom;acidic hydrogen atoms.The metal addenda atoms linked by oxygen atoms form a cluster with the hetero-atom inside bonded via oxygen atoms. Examples with more than one type of metal addenda atom in the cluster are well known. The conjugate anion of a heteropoly acid is known as a polyoxometalate.Due to the possibilities of there being different combinations of addenda atoms and different types of hetero atoms there are a lot of heteropolyacids. Two of the better known groups of these are based on the Keggin, HnXM12O40, and Dawson, HnX2M18O62, structures.Some examples are:H4Xn+M12O40, X = Si, Ge; M = Mo, WH3Xn+M12O40, X = P, As; M = Mo, WH6X2M18O62, X=P, As; M = Mo, WThe heteropolyacids are widely used as homogeneous and heterogeneous catalysts, particularly those based on the Keggin structure as they can possess qualities such as good thermal stability, high acidity and high oxidising ability. Some examples of catalysis are:Homogeneous acid catalysishydrolysis of propene to give propan-2-ol by H3PMo12O40 and H3PW12O40Prins reaction by H3PW12O40polymerisation of THF by H3PW12O40Heterogeneous acid catalysisdehydration of propan-2-ol to propene and methanol to hydrocarbons by H3PW12O40reformation of hexane to 2-methylpentane (isohexane) by H3PW12O40 on SiO2Homogeneous oxidationcyclohexene + H2O2 to adipic acid by the mixed addenda H3PMo6V6O40ketone by O2 to acid and aldehyde by mixed addenda H5PMo10V2O40Heteropolyacids have long been used in analysis and histology and are a component of many reagents e.g. the Folin-Ciocalteu reagent, folins phenol reagent used in the Lowry protein assay and EPTA, ethanolic phosphotungstic acid.".
- Q3733706 thumbnail Phosphotungstate-3D-polyhedra.png?width=300.
- Q3733706 wikiPageWikiLink Q1053.
- Q3733706 wikiPageWikiLink Q10693.
- Q3733706 wikiPageWikiLink Q11158.
- Q3733706 wikiPageWikiLink Q11344.
- Q3733706 wikiPageWikiLink Q11426.
- Q3733706 wikiPageWikiLink Q1411716.
- Q3733706 wikiPageWikiLink Q14982.
- Q3733706 wikiPageWikiLink Q150440.
- Q3733706 wikiPageWikiLink Q151324.
- Q3733706 wikiPageWikiLink Q16392.
- Q3733706 wikiPageWikiLink Q171877.
- Q3733706 wikiPageWikiLink Q193099.
- Q3733706 wikiPageWikiLink Q19600.
- Q3733706 wikiPageWikiLink Q209445.
- Q3733706 wikiPageWikiLink Q2246598.
- Q3733706 wikiPageWikiLink Q267374.
- Q3733706 wikiPageWikiLink Q278332.
- Q3733706 wikiPageWikiLink Q3500623.
- Q3733706 wikiPageWikiLink Q357415.
- Q3733706 wikiPageWikiLink Q3604564.
- Q3733706 wikiPageWikiLink Q36534.
- Q3733706 wikiPageWikiLink Q413328.
- Q3733706 wikiPageWikiLink Q473222.
- Q3733706 wikiPageWikiLink Q556.
- Q3733706 wikiPageWikiLink Q629.
- Q3733706 wikiPageWikiLink Q670.
- Q3733706 wikiPageWikiLink Q674.
- Q3733706 wikiPageWikiLink Q722.
- Q3733706 wikiPageWikiLink Q743.
- Q3733706 wikiPageWikiLink Q77213.
- Q3733706 wikiPageWikiLink Q82264.
- Q3733706 wikiPageWikiLink Q8509267.
- Q3733706 wikiPageWikiLink Q871.
- Q3733706 wikiPageWikiLink Q902883.
- Q3733706 wikiPageWikiLink Q903156.
- Q3733706 wikiPageWikiLink Q910291.
- Q3733706 comment "A heteropoly acid is a class of acid made up of a particular combination of hydrogen and oxygen with certain metals and non-metals.".
- Q3733706 label "Heteropoly acid".
- Q3733706 depiction Phosphotungstate-3D-polyhedra.png.