Cobaltate , dihydrate

Cobalt(II) oxalate [814-89-1], C0C2O4, is a pink to white crystalline material that absorbs moisture to form the dihydrate. It precipitates as the tetrahydrate on reaction of cobalt salt solutions and oxaUc acid or alkaline oxalates. The material is insoluble in water, but dissolves in acid, ammonium salt solutions, and ammonia solution. It is used in the production of cobalt powders for metallurgy and catalysis, and is a stabilizer for hydrogen cyanide. 

Chemical Designations - Synonyms Cobalt (II) Chloride Cobaltous Chloride Cobaltous Chloride Dihydrate Cobaltous Chloride Hexahydrate Chemical Formula CoClj,... 

Tetrasodium (Cobalt(II) 2,9,16,23-tetrasuIfophthaIocyanine] Dihydrate (4) Single Procedure 421... 

Urea (3.2 g, 53 mmol), (NH4)2Mo04 (0.126g, 0.6 mmol), and pyridine-2,3-dicarboxylic acid (l.Og, 6 mmol) were ground together until homogenous. The lnixlure was stirred in 1,2,4-trichlorohenzene (40 mL) for 1 h at 156-160=C. A ground mixture of cobalt(II) oxalate dihydrate (1.1 g, 6 mmol) and urea (2.5 g, 42 mmol) was slowly added under N2. The temperature was maintained at 205-210 C for 3.5 h. On completion, excess 1,2,4-trichlorobenzene was removed by distillation under reduced pressure. The crude product was washed with benzene (100 mL), crushed and washed successively with EtOH, warm H20, warm 5% aq NaOH, warm H20, warm 2.5% HC1, and warm H20, and dried at 80 C yield 0.882 g (45%). 

C10H21CoN4O13P - 2 H20 Penta-aquo-cobalt(II)-inosine 5 -phosphate, dihydrate IMPCOH 34 366... 

For the hydrosilylation reaction various rhodium, platinum, and cobalt catalysts were employed. For the further chain extension the OH-functionalities were deprotected by KCN in methanol. The final step involved the enzymatic polymerization from the maltoheptaose-modified polystyrene using a-D-glucose-l-phosphalc dipotassium salt dihydrate in a citrate buffer (pH = 6.2) and potato phosphorylase (Scheme 59). The characterization of the block copolymers was problematic in the case of high amylose contents, due to the insolubility of the copolymers in THF. 

In another spectrophotometric procedure Motomizu [224] adds to the sample (2 litres) 40% (w/v) sodium citrate dihydrate solution (10 ml) and a 0.2% solution of 2-ethylamino-5-nitrosophenol in 0.01 M hydrochloric acid (20 ml). After 30 min, add 10% aqueous EDTA (10 ml) and 1,2-dichloroethane (20 ml), mechanically shake the mixture for 10 minutes, separate the organic phase and wash it successively with hydrochloric acid (1 2) (3 x 5 ml), potassium hydroxide (5 ml), and hydrochloric acid (1 2) (5 ml). Filter, and measure the extinction at 462 nm in a 50 mm cell. Determine the reagent blank by adding EDTA solution before the citrate solution. The sample is either set aside for about 1 day before analysis (the organic extract should then be centrifuged), or preferably it is passed through a 0.45 xm membrane-filter. The optimum pH range for samples is 5.5 - 7.5. From 0.07 to 0.12 p,g/l of cobalt was determined there is no interference from species commonly present in seawater. 

Three color changes were observed blue, violet and red. From the information provided, the blue form appeared to be the anhydride, CoCl2. When exposed briefly to air containing water vapor, the anhydrous cobalt chloride turned violet, CoCl2 2H20. Upon further standing in air, the dihydrate was converted to the fully hydrated form, CoCl2 6 H20. The color of the anhydride-hydrate depended upon the relative humidity of the air to which it was exposed. 

Synonym Gamma-Chloropropylene Oxide 3-Chloro-1,2-Propylene Oxide Chlorosulfonic Acid Chlorothene Chiorotoluene, Alpha Alpha-Chlorotoluene Omega-Chlorotoluene Chlorotrifluoroethylene Chlorotrimethylsilane Chlorsulfonic Acid Clilorylen Clip Chromic Acid Chromic Anhydride Chromic Oxide Chromium (VI) Dioxychloride Chromium Oxychloride Chromium Trioxide Chromyl Chloride Cianurina Citric Acid Citric Acid, Diammonium Salt Clarified Oil Clorox Cc Ral Coal Tar Oil Cobalt Acetate Cobalt Acetate Tetrahydrate Cobalt (II) Acetate Cobalt Chloride Cobalt (II) Chloride Cobaltous Acetate Cobaltous Chloride Cobaltous Chloride Dihydrate Cobaltous Chloride Hexahydrate Cobaltous Nitrate Cobaltous Nitrate Hexahydrate Cobaltous Sulfate Heptahydrate Cobalt Nitrate Cobalt (II) Nitrate Cobalt Sulfate Compound Name Epichlorohydrin Epichlorohydrin Chlorosulfonic Acid Trichloroethane Benzyl Chloride Benzyl Chloride Benzyl Chloride Trifluorochloroethylene Trimethylchlorosilane Chlorosulfonic Acid Trichloroethylene Cumene Hydroperoxide Chromic Anhydride Chromic Anhydride Chromic Anhydride Chromyl Chloride Chromyl Chloride Chromic Anhydride Chromyl Chloride Mercuric Cyanide Citric Acid Ammonium Citrate Oil Clarified Sodium Hypochlorite Coumaphos Oil Coal Tar Cobalt Acetate Cobalt Acetate Cobalt Acetate Cobalt Chloride Cobalt Chloride Cobalt Acetate Cobalt Chloride Cobalt Chloride Cobalt Chloride Cobalt Nitrate Cobalt Nitrate Cobalt Sulfate Cobalt Nitrate Cobalt Nitrate Cobalt Sulfate... 

Cobalt Pyroarsenate, CoaAs207, is formed when cobalt oxide is fused with potassium metarsenate violet crystals are obtained on cooling.5 A dihydrate, Co2As207.2H20, has also been described.6... 

Cobaltous oxalate dihydrate, CoC 04-2H 0 tpink). is obtained by adding oxalic acid or an alkaline oxalate to a cobaltous salt solution. This is the commercial form of tile salt and is important as the starting material in ihe preparation of cobalt metal powders. 

Although square-planar configuration is customarily considered classical for v/c-dioximate of nickel(II), attempts have been made repeatedly over the years for preparing the above complexes in other configurations also. By employing weakly polar solvents and some other variations, success has been claimed in the preparation of mono(dioxime) complexes of nickel(II).42,43 The dichloro-bis(l,2-cyclohexanedione dioximato)nickel(II) has been shown to have an octahedral vie structure.44 Examples of tris(dioxime) complexes of transition metals in general45"18 and of bivalent atoms40,47 in particular are rare and structural details of only a tris(dioxime) complex of cobalt(III) are known.48 In a more recent publication,49 the crystal structure of tris(l,2-cyclohexanedione dioximo)nickel(II) sulfate dihydrate has been elucidated. 

Potassium phosphate monobasic Magnesium sulfate heptahydrate Calcium chloride dihydrate Zinc sulfate heptahydrate Ferric sulfate heptahydrate Copper sulfate pentahydrate Cobalt(II) chloride hexahydrate Perchloric acid Potassium hydrocarbonate... 

No method of prepn is given in Refs 2 or 3. Accd to Ref 4, p581, it cannot be prepd by dehydration of its hexahydrate, Co(Cl04)2.6H20, or of dihydrate, Co(C104)2.2H20. Cobaltic perchlorate, Co(ClOA)3, exists only in solns (Ref 4, P583)... 

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