Zinc metavanadate

Zinc Metavanadate, Zn(V03)2.2H20, forms brilliant, pale yellow, cubic or rhombic crystals when zinc nitrate is added to a neutral solution of ammonium metavanadate and the mixture is concentrated.4 It has also been obtained electrolytically.5... 

Lead Metavanadate, Pb(VOg)2.—Acid solutions of vanadates on being treated with lead salts give rise to yellow basic vanadates the composition of which varies with the conditions. The precipitation of normal lead vanadate is, therefore, difficult. It has been accomplished by the addition of lead acetate to ammonium metavanadate solution in the presence of acetic acid.2 The lead precipitates contain all the vanadic acid originally present in solution, and precipitation of vanadates with lead salts has, therefore, been employed for the quantitative estimation of vanadium.3 The mineral deschenite consists chiefly of lead metavanadate a portion of the lead is, however, frequently replaced by zinc.4... 

The use of certain vanadium compounds as catalysts has been increasing. Vanadium oxy trichloride is a catalyst in making ediylene-propylene rubber. Ammonium metavanadate and vanadium pentoxide aie used as oxidation catalysts, particularly in the production of polyamides, such as nylon, in the manufacture of H>S04 by the contact process, in the production of phdialic and maleic anhydrides, and in numerous other oxidation reactions, such as alcohol to acetaldehyde, anthracene to anthraquinone, sugar to oxalic acid, and diphenylamine to carbazole. Vanadium compounds have been used for many years 111 die ceramics field for enamels and glazes. Colors are produced by various combinations of vanadium oxide and silica, zirconia, zinc, lead, tin, selenium, and cadmium. Vanadium intermediate compounds also are used in the making of aniline Mack used by the dye industry... 

Mg as magnesium oxide Fe as Ferrous fumarate Zn as zinc oxide Ti as titanium dioxide Cu as cupric oxide Mo as sodium molybdate I as potassium iodide V as sodium metavanadate Sn as tin(II) chloride... 

A) Oxidation states of transition elements. In four large test tubes place about 20 ml of dilute solutions of titanic chloride, ammonium metavanadate, potassium dichromate, and ammonium molybdate. Add to each about 10 ml of concentrated hydrochloric acid and several grams of granulated or mossy zinc. Set under the draft. Note all the color changes and interpret them by means of ionic equations. 

Preparation. Ammonium metavanadate, NH4VO3, is dissolved in aqueous NaOH and then added to hydrochloric acid. The solution is then stirred with heavily amalgamated zinc. The solution of VCI2 thus obtained is stable on storage for several months. 

Sodium aluminate Sodium diacetate Sodium formate Sodium metavanadate Sodium thiosulfate anhydrous Zinc nitrate... 

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