Sodium orthovanadate
{{chembox
| ImageFile = Na3VO4dihydrate.tif
| Verifiedfields = changed
| Watchedfields = changed
| verifiedrevid = 448231456
| IUPACName = Sodium vanadate(V)
| OtherNames = Sodium vanadium oxide
|Section1={{Chembox Identifiers
| CASNo_Ref = {{cascite|correct|CAS}}
| CASNo = 13721-39-6
| CASNo_Comment = (anhydrous)
| UNII_Ref = {{fdacite|correct|FDA}}
| UNII = 7845MV6C8V
| PubChem = 61671
| ChEMBL_Ref = {{ebicite|changed|EBI}}
| ChEMBL = 179166
| ChEBI = 35607
| RTECS = YW1120000
| InChI = 1S/3Na.4O.V/q3*+1;;3*-1;
| SMILES = [O-] [V](=O)([O-])[O-].[Na+].[Na+].[Na+]
}}
|Section2={{Chembox Properties
| Formula = {{chem2|Na3VO4}}
| MolarMass = 183.908 g/mol
| Appearance = white powder
| Density = 2.16 g/cm3, solid
| Solubility = 22.17 g/100 mL
| SolubleOther = insoluble in ethanol
| MeltingPtC = 858
}}
|Section3={{Chembox Structure
| CrystalStruct = cubic
}}
|Section5={{Chembox Thermochemistry
| DeltaHf = −1757 kJ/mol
| Entropy = 190 J/mol K
| HeatCapacity = 164.8 J/mol K
}}
|Section7={{Chembox Hazards
| ExternalSDS =
| MainHazards = Harmful.
| NFPA-H = 3
| NFPA-F = 0
| NFPA-R = 0
| FlashPt = Non-flammable
| LD50 = 330 mg/kg (oral, rat)
}}
Sodium orthovanadate is the inorganic compound with the chemical formula {{chem2|Na3V O4}}. It forms a dihydrate {{chem2|Na3VO4*2H2O}}. Sodium orthovanadate is a salt of the {{chem2|VO4(3-)}} oxyanion. It is a colorless, water-soluble solid.{{Greenwood&Earnshaw}}
Synthesis and structure
Sodium orthovanadate is produced by dissolving vanadium(V) oxide in a solution of sodium hydroxide:
:{{chem2|V2O5 + 6 NaOH → 2 Na3VO4 + 3 H2O}}
The salt features tetrahedral {{chem2|VO4(3-)}} anion centers linked to octahedral {{chem2|Na+}} cation sites.{{cite journal|last1=Kato|first1= K.|last2= Takayama-Muromachi|first2= E. |title=Die Struktur des Trinatriumvanadattrihydrats|trans-title=The structure of trisodium vanadate trihydrate|journal=Acta Crystallogr.|year=1987 |volume=C43 |issue= 6|pages=1030–1032|doi=10.1107/S0108270187093120|bibcode= 1987AcCrC..43.1030K|url=http://journals.iucr.org/c/issues/1987/06/00/a27117/a27117.pdf}}
Condensation equilibria
Like many oxometalates, orthovanadate is subject to a number of reactions, which have been analyzed by 51V NMR studies. At high pH, {{chem2|VO4(3-)}} ions exist in equilibrium with {{chem2|HVO4(2-)}}.{{cite book |doi=10.1016/S0066-4103(07)62002-X|title=Vanadium-51 NMR|series=Annual Reports on NMR Spectroscopy|year=2007|last1=Rehder|first1=D.|last2=Polenova|first2=T.|last3=Bühl|first3=M.|volume=62|pages=49–114|isbn=9780123739193}} At lower pH's, condensation ensues to give various polyoxovanadates. Ultimately, decavanadate is formed.{{cite journal|author1-link=Walter G. Klemperer|first1=W. G. |last1=Klemperer |author2-link=Omar M. Yaghi|first2=O.|last2=Yaghi |title=Tetrabutylammonium Trihydrogen Decavanadate(V) |journal=Inorg. Synth.|date= 1983 |volume=27 |page=83|doi=10.1002/9780470132586.ch15}}
Biochemistry
Vanadates exhibit a variety of biological activities, in part because they serve as structural mimics of phosphates.{{cite journal|last1=Korbecki|first1= Jan|last2= Baranowska-Bosiacka|first2= Irena|last3= Gutowska|first3= Izabela|last4= Chlubek|first4= Dariusz |title=Biochemical and medical importance of vanadium compounds |journal=Acta Biochim. Pol. |date=2012 |volume=59 |issue= 2|pages=195–200|doi= 10.18388/abp.2012_2138|pmid= 22693688|url=http://www.actabp.pl/pdf/2_2012/195.pdf|doi-access= free}}{{cite encyclopedia|last1=Crans|first1= D. C.|last2= Chatterjee|first2= P. B.|chapter=Vanadium biochemistry |editor1-last=Reedijk|editor1-first= Jan|editor2-last= Poeppelmeier|editor2-first= Kenneth |encyclopedia=Comprehensive Inorganic Chemistry II |date=2013 |volume=3 |pages=323–342|doi=10.1016/B978-0-08-097774-4.00324-7|isbn=978-0-08-097774-4|title= Comprehensive Inorganic Chemistry II: From Elements to Applications}} It acts as a competitive inhibitor of ATPases, alkaline and acid phosphatases, and protein-phosphotyrosine phosphatases, and its inhibitory effects can be reversed by dilution or the addition of ethylenediaminetetraacetic acid (EDTA).{{cite web|url=https://www.neb.com/products/p0758-sodium-orthovanadate-activated-vanadate#Product%20Information|title=Sodium Orthovanadate (Vanadate) {{!}} NEB|last=Biolabs|first=New England|website=www.neb.com|language=en|access-date=2018-09-07}}
Orthovanadate is activated by boiling and adjusting pH to ~10; this depolymerizes decavanadate into the active inhibitor, monovanadate.{{cite web|url=https://www.sigmaaldrich.com/content/dam/sigma-aldrich/docs/Sigma/Product_Information_Sheet/1/s6508pis.pdf|title=Sodium orthovanadate|website=Sigma-Aldrich|access-date=September 7, 2018}}
References
{{reflist}}
See also
{{Sodium compounds}}