Sodium metavanadate

Sodium metavanadate ;
Names:	sodium metavanadate; sodium vanadate; sodium trioxovanadate; vanadum-sodium trioxide;
Formula:	NaVO3 (anhydrous); NaVO3 · 2H2O (dihydrate);
Molar mass:	121.929 g/mol (anhydrous); 157.959 g/mol (dihydrate);
Density:	2.85 g/cm3 (anhydrous); 2.79 g/cm3 (dihydrate);
Crystal system:	monoclinic (anhydrous); a=10.552 Å, b=9.468 Å, c=5.879 Åα=90°, β=108.47°, γ=90°; orthorhombic (dihydrate); a=14.147 Å, b=3.6496 Å, c=5.364 Åα=90°, β=90°, γ=90°;
Shapes:	https://en.crystalls.info/w/uploads/media/f/fc/Spherolit.json Spherolit https://en.crystalls.info/w/uploads/media/5/52/Needle.json Needle ;
Color:	colorless; pale yellow surface; shimmers in the light;
Melting point:	632 °C905.15 K <br />1,169.6 °F <br />1,629.27 °R <br /> (anhydrous);
Magnetic properties:	diamagnetic;
Stability:	stable (monohydrate); slightly hygroscopic (anhydrous);
Hardness:	fragile;
Toxicity:	highly toxic; LD50=98mg/kg

Description

Inorganic compound, salt of alkaline metal sodium and inorganic metavanadic acid. From water solutions crystallizes as dihydrate.

Minerals

Occurs in nature as munirite and metamunirite minerals.

Precursors

Reaction between sodium hydroxide and vanadium pentaoxide

Chemical equation:

2NaOH + V₂O₅ = 2NaVO₃ + H₂O

For preparation of 100.00g of sodium metavanadate

dihydratedihydrate
anhydrous

а 57.57g of vanadium pentaoxide and 25.32g of sodium hydroxide is required.

Add to flask with hot concentrated solution of hydroxide sodium small amount of vanadium pentaoxide with intense stirring. Heat it to 100°C for few minutes for reaction completion and then filter out. For purifying compound from hydroxide add large amount of cold ethanol, acetone or toluene to solution, salt will settle to the bottom in the form of fine crystals or powder. Filter precipitate and wash it with small amount of the same solvent, then filter the solution and use it for crystal growing.

Reaction between sodium hydroxide and ammonium metavanadate

Chemical equation:

NaOH + NH₄VO₃ = NaVO₃ + H₂O + NH₃↑

For preparation of 100.00g of sodium metavanadate

dihydratedihydrate
anhydrous

а 74.06g of ammonium metavanadate and 25.32g of sodium hydroxide is required.

Add to the flask saturated solution of sodium hydroxide and then add small parts of hot ammonium metavanadate solution with heating and stirring. Emission of large amount of ammonia will begin.Attention, exuding ammonia irritates eyes and lungs! The synthesis should be carried out only in a fume hood or outdoors!

Notes

There are some redox processes occurring in solution, because of them the crystal surface could be slightly yellow.

Storage conditions

Keep in its original form or under several layers of varnish at average humidity and room temperature. Do not keep crystals near heaters.

Solubility

TableGraph

Temperature	g/`100,00` g water
Temperature	(anhydrous)	(dihydrate)
20°C293.15 K <br />68 °F <br />527.67 °R <br />	`19.3`	`~26.5`
25°C298.15 K <br />77 °F <br />536.67 °R <br />	`21.1`	`~29.2`
70°C343.15 K <br />158 °F <br />617.67 °R <br />	`38.8`	`~56.8`
80°C353.15 K <br />176 °F <br />635.67 °R <br />	`40.8`	`~60.1`

Insoluble in ethanol, methanol, acetone, toluene and isopropanol.

Gallery

Video

Sources

Vanadates
Potassium metavanadate (KVO₃) • Sodium decavanadate (Na₆V₁₀O₂₈) • Sodium metavanadate (NaVO₃)

Sodium compounds
Salts	Sodium acetate (NaCH₃COO) • Sodium bromide (NaBr) • Sodium citrate (Na₃C₃H₅O(COO)₃) • Sodium chlorate (NaClO₃) • Sodium chloride (NaCl) • Sodium cyclamate (C₆H₁₂NNaO₃S) • Sodium decavanadate (Na₆V₁₀O₂₈) • Sodium ethilate (NaC₂H₅O) • Sodium glutamate (NaC₅H₈NO₄) • Sodium hydrocarbonate (NaHCO₃) • Sodium hydrosulfate (NaHSO₄) • Sodium iodide (NaI) • Sodium metavanadate (NaVO₃) • Sodium niobate (NaNbO₃) • Sodium nitrate (NaNO₃) • Sodium oxalate (Na₂C₂O₄) • Sodium para-aminosalicylate (C₇H₆NNaO₃) • Sodium perchlorate (NaClO₄) • Sodium saccharinate (C₇H₄NaNO₃S) • Sodium sulfate (Na₂SO₄) • Sodium sulfide (Na₂S) • Sodium tetraborate (Na₂B₄O₇) • Sodium thiosulfate (Na₂S₂O₃) • Sodium trichloroacetate (NaCCl₃COO) • Sodium trioxalatoaluminate (Na₃[Al(C₂O₄)₃]) • Sodium tungstate (Na₂WO₄)
Double salts	Potassium-sodium tartrate (KNaC₄H₄O₆) • Sodium-ammonium sulfate (NaNH₄SO₄) • Uranyl-sodium acetate (NaUО2(CH₃COO)₃) • Uranyl-zinc-sodium acetate (NaZn(UO₂)₃(CH₃COO)₉) • Zinc-sodium sulfate (Na₂Zn(SO₄)₂)
Adducts	Glucose and sodium bromide adduct (2C₆H₁₂O₆ · NaBr) • Glucose and sodium chloride adduct (2C₆H₁₂O₆ · NaCl) • Urea and sodium chloride adduct (CO(NH₄)₂ · NaCl)
Complex compounds	Sodium dicarbonatocuprate(II) (Na₂[Cu(CO₃)₂]) • Sodium dioxalatocuprate(II) (Na₂[Cu(C₂O₄)₂]) • Sodium ethylenediaminetetraacetate-ferrate(III) (Na[Fe((OOCCH₂)₂N(CH₂)₂N(CH₂COO)₂)]) • Sodium hexacyanoferrate(II) (Na₄[Fe(CN)₆]) • Tripotassium-sodium hexacyanoferrate(II) (K₃Na[Fe(CN)₆]) • Sodium hexafluorosilicate (Na₂[SiF₆]) • Sodium nitroprusside (Na₂[Fe(CN)₅NO]) • Sodium trioxalatochromate(III) (Ns₃[Cr(C₂O₄)₃]) • Dipotassium-sodium trioxalatoferrate(III) (K₂Na[Fe(C₂O₄)₃]) • Potassium-sodium trioxalatoferrate(III) (K₅Na[Fe(C₂O₄)₃]₂) • Sodium trioxalatoferrate(III) (Na₃[Fe(C₂O₄)₃])

Sodium metavanadate
Names:	sodium metavanadate sodium vanadate sodium trioxovanadate vanadum-sodium trioxide
Formula:	NaVO₃ (anhydrous) NaVO₃ · 2H₂O (dihydrate)
Molar mass:	121.929 g/mol (anhydrous) 157.959 g/mol (dihydrate)
Density:	2.85 g/cm³ (anhydrous) 2.79 g/cm³ (dihydrate)
Crystal system:	monoclinic (anhydrous) a=10.552 Å, b=9.468 Å, c=5.879 Åα=90°, β=108.47°, γ=90° orthorhombic (dihydrate) a=14.147 Å, b=3.6496 Å, c=5.364 Åα=90°, β=90°, γ=90°
Shapes:	Spherolit Needle
Color:	colorless pale yellow surface shimmers in the light
Melting point:	632 °C905.15 K <br />1,169.6 °F <br />1,629.27 °R <br /> (anhydrous)
Magnetic properties:	diamagnetic
Stability:	stable (monohydrate) slightly hygroscopic (anhydrous)
Hardness:	fragile
Toxicity:	highly toxic LD₅₀=98mg/kg