Barium molybdate

Band theory, 27 2 Barium, in oil, Tliill Barium molybdate, 27 205 Base metal... 

Alkhazov et al. (99-101) compared the physicochemical properties and catalytic activities of Group II element molybdates. The calcium, strontium, cadmium, and barium molybdates have a scheelite structure... 

When the central atom is not a transition element, a soluble molybdate or tungstate may be dissolved with a soluble salt containing the central atom in the appropriate oxidation state. The mixture is then acidified to an appropriate pH range. Sometimes barium molybdate is mixed with a sulfuric acid solution containing the central atom, or molybdenum trioxide is boiled with a solution containing the atom. 

The 6-molybdoiodates or 6-tungstoiodates are prepared similarly. The free acid is made directly from periodate and molybdenum trioxide. It may also be prepared by reaction between barium molybdate, periodic acid, and sulfuric acid. Its neutralization curve has been reported147. The yellow free acid evolves gaseous products upon isolation27 and, therefore, probably undergoes some decomposition. 

Barium Molybdates.—The normal salt BaMo04 is precipitated -on addition of aqueous barium chloride to a neutral or ammoniacal solution of ammonium molybdate. By fusion of a mixture containing sodium molybdate (2 parts), barium cliloride (6 parts), and sodium chloride (3 parts), barium molybdate may be obtained as a crystalline mass consisting of tetragonal pyramids with a c=l 1-6232, and of density 4-64i8 at 19-5° C. It is practically insoluble in water, 1 part, of the salt dissolving in 17,200 parts of the solvent at 23° C. It is more readily soluble in presence of ammonium nitrate. 

Barium molybdate (IV) is an intensely colored purple-red powder, and SrMoOs is a more intensely colored brick-red powder. The colors of both compound.s become somewhat... 

Barium molybdate BaMoO, 3,54 10- Cesium periodate CslO 5.16 10-5... 

If larger quantities are desired, the wet method of silicomolybdate decomposition is more convenient. The latter complex is treated with barium hydroxide solution saturated at low temperature. (To avoid working with excessive quantities of liquid, part of the Ba(OH)a can be added as the solid.) The amount added must exceed by 20% the amount required to decompose the complex into barium molybdate, barium silicate and RbOH (CsOH). The mixture is then boiled for thirty minutes. Flame gases containing CO3 should not come in contact with the mixture or large amoimts of Ba(OH)a will be converted to worthless BaCOa. The barium molybdate and barium silicate which separate are not filtered off imtil after the reaction mixture has cooled. The filtrate is then saturated with C03 and boiled for fifteen minutes. The BaCOa precipitate is filtered off and the filtrate is evaporated with simultaneous addition of hydrochloric acid. The residue contains RbCl and CsCl free of Mo and Ba. 

Barium metatitanate. See Barium titanate Barium molybdate... 

Barium molybdate Silver electronic potting compounds Boron trifluoride electronic research Cobalt potassium cyanide electronic transfer molding compounds 3,3, 4,4 -Benzophenone tetracarboxylic dianhydride Pyromellitic dianhydride electronic/communication equip. 

Barium molybdate optical fiber materials Quartz optical glass... 

Aminotrimethylene phosphonic acid Arsenic disulfide Arsenic pentasulfide Barium molybdate Barium sulfate Basic violet 1 Basic violet 10 Bone black Cadmium red Cadmium sulfide Calcium fluoride Calcium phosphate dibasic Calcium sulfate Chrome antimony titanium buff Cobalt... 

Silica, fumed Tartrazine Titanium dioxide Ultramarine blue Ultramarine violet pigment, protective coatings Barium molybdate... 

Isac, J. and Ittyachen, M. A. Growth and characterization of rare-earth mixed single crystals of samarium barium molybdate. Bulletin of Materials Science, 5(4), 349-353(1992). 

Isac, J. Ittyachen, M. A. Raju, K. S. (1996). Praseodymium barium molybdate-its growth and structural characterization Bull. Mater. Sci. 19., 3., (October 1995) 495-504, ISSN 0250-4707. 

Kurien, K. V. Ittyachen, M. A. (1979). Growth kinetics and habit modification of barium molybdate single crystals in silica gel.. Cryst. Growth. 47., 5-6., (November-December 1979) 743-745, ISSN 0022-0248. 

Ryu, J.H. Yoon, J.W. Lim, C.S. Shim, K.B. (2005b). Microwave-assisted synthesis of barium molybdate by a citrate complex method and oriented aggregation. Mater. Res. Bull. 40., 9., (September 2005) 1468 -1476. 

Afimasiev, P. (2007) Molten salt synthesis of barium molybdate and tungstate microcrystals. Mater. Lett, 61,4622-4626. 

Kurosaki, K., Oyama, T., Muta, H., Uno, M., and Yamanaka, S. Thermoelectric properties of perovskite type barium molybdate. J. Alloys Compd. 2004, 372, 65-69. 

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