Cupric hydroxide, preparation

Prepare the cupric hydroxide by dissolving 2 g. of copper sulphate in about too ml. of water, and adding with stirring 16 ml. of N.NaOH solution. Filter off the precipitate and wash thoroughly with water. 

Allied to the cuprammmes is Schweizer s reagent, which is prepared by dissolving cupric hydroxide in an aqueous solution of ammonia, when a deep blue liquid is obtained which has the property of dissolving... 

The copper phthalate eluant was prepared by mixing a solution of cupric acetate with an excess of potassium hydroxide and filtering the resulting cupric hydroxide precipitate. The cupric hydroxide precipitate was then mixed with an equimolar amount of phthalic acid and heated gently overnight to produce copper phthalate. 

Cupric chlorate, Cu(C108)2.—The chlorate is prepared by dissolving cupric hydroxide or carbonate in chloric acid, or by the interaction of cupric sulphate and barium chlorate. On evaporation of the solution it separates in the form of the tetrahydrate, which melts and decomposes at 73° C.13... 

Cupric iodate, Cu(I03)2.—Solution of cupric hydroxide or carbonate in a solution of iodic acid yields the iodate, which is known in the anhydrous form,1 and as monohydrate,2 and dihydrate.3 From excess of a solution of potassium iodate, cupric nitrate precipitates the pale-blue monohydrate. At 25° C. its solubility is 3-3 X 10-3 gram-molecules per litre of water.4 A basic iodate, Cu(I03)2,Cu(0H)2, has also been prepared.5... 

Cupric hydroxide, Cu(OH)2.—The hydroxide has been prepared in crystalline form by the action of a solution of caustic alkali on a basic cupric nitrate 2 and a basic cupric sulphate,3 and also by other methods.4 A hydrogel of varying composition is precipitated by addition of alkali to solutions of cupric salts.5 Unlike the colloidal form, the blue crystalline variety is stable at 100° C. A solid, colloidal variety has been obtained 6 as blackish-blue, brittle lamellae which dissolve in water to form the original solution. An amorphous modification is precipitated from ammoniaeal copper solutions by the action of alkali-metal hydroxides.7... 

P61igot, Compt. rend., 1861, 53, 209 Villiers, ibid., 1895, 120, 322. KoJalschutter and Tusoher Zeitsch. anorg. Chem., 1920, in, 193) have summarized tho methods employed in the preparation of cupric hydroxide, and described the properties of the various products obtained. 

The results with Cu - and Cu -TSMs (27) are also shown in Table III. Cu -TSM was obtained similarly to Cu -TSM using the Cu(I) ammine complex salt in the ion-exchange reaction. Cu -TSM, copper supported on TSM, was prepared by calcination and subsequent hydrogen reduction of an oligomeric cupric hydroxide intercalate, which had been obtained by precipitating the hydroxide into the interlayer spaces of TSM after the titration method developed by Yamanaka and Brindley (8). The catalytic activity of Cu -TSM is so poor as to be less than one-tenth of that of Cu -TSM, although the molar content of Cu is about twice as high. Because a weak sig-... 

Prepare a small amount of cupric hydroxide by adding 1 ml of copper sulfate to a drop or two of sodium hydroxide solution. Add 2 ml of glycine and shake. Explain. 

T 1) an improved method is recommended. The silk is dissolved in a cupri-ethylenediamine solution which is prepared by shaking together for two hours 70 g of copper hydroxide and one litre of 8 per cent ethylene-diamine which has been adjusted to pH 4-5 by the addition of acid. The undissolved cupric hydroxide is separated by filtering through asbestos mixed with kieselguhr. The copper in the filtrate is determined by titration with thiosulphate of the iodine liberated from potassium iodide, and the necessary adjustment is made to bring it to the equivalent of 5-95 to 6-05 per cent of cupric hydroxide. This solution can be kept for some months in, a dark bottle in a cool place. 

All coppei -nickel catalysts were prepared from the magnetically pure copper which was itself completely inactive in the hydrogenation of benzene under the conditions described below. Cupric hydroxide was precipitated from a nitrate solution by dilute ammonium hydroxide solution so that the supernatant liquid was faintly colored by the copper-ammonia complex. The precipitate was filtered and washed. Nickel nitrate in water solution was now added in the proportion desired, and the mixture was stirred to a paste of even consistency. It was dried at 95°, ignited at 180° for 36 hours, and finally at 400° for 20 hours. The oxide mixture was reduced in purified hydrogen at 150° for 20 hours. Most finished catalysts contained 1.0 per cent of nickel. 

Single phase cuprous oxide (14 nm) was prepared by °Co gamma irradiation of deoxygenated aqueous solutions containing copper sulfate, propan-2-ol, surfactant sodium dodecyl sulfate, and acetate buffer at pH 4-4.5 (Zhu et al. 1994). In the absence of buffer (pH 3-3.5), mixture of copper and cuprous oxide was observed. Most probably, three competitive reactions occur radiation reduction (Equations (4.6) and (4.8)), dismntation of cuprous ions (Equation 4.9), and the formation of cuprous hydroxide, which decomposes to cuprous oxide (Equation 4.10). In buffered solutions, the reduction and dismntation of cnprons ions are completely suppressed. Since cuprous hydroxide is very unstable, it decomposes rapidly to cnprous oxide immediately after its formation. On the other hand, the precipitate of cupric hydroxide Cu(OH)2 forms in the solution of pH >5. 

Singh published details of the preparation of cuprous azide from cuprous chloride dissolved in saturated aqueous sodium chloride in presence of a small amount of potassium bisulfite and acidified by acetic acid. The cuprous azide was precipitated by addition of aqueous sodium azide [76,110]. Another way of preparing CuNs is based on the reaction of freshly prepared cuprous oxide (from cupric hydroxide and... 

The composition of the product prepared in a neutral envirraunent of cupric chloride or sulfate is close to theory (the ratio of C/Cu = 1.98). If the reactant is a cupric tartrate in an acidic enviromnent then cuprous acetylide is the final product due to the reducing properties of tartaric acid [50]. Cupric acetylide is also produced directly by the reactirm of calcium carbide in aqueous solutions with cupric salts. Calcium hydroxide and cupric hydroxide, which co-precipitate together with cupric acetylide, can be dissolved by adding dilute acetic acid [48]. 

COPPER OXIDE. (Cuprous oxide.) CUjO. Mol. wt. 143.08 density 6.0 g/cm m.p. 1235°C. Cubic red crystals insoluble in water, soluble in HCl, NH4CI and NH4OH. Prepared by the oxidation of copper, by the addition of bases to cuprous chloride or by the action of glucose on cupric hydroxide. 

The special reducing agent (a solution containing cupro-ammonia ions) is first prepared. Dissolve 63 g. of crystallised copper sulphate in 250 ml. of water in a 1-Utre heaker, add 100 ml. of concentrated ammonium hydroxide solution (sp. gr. 0-88), and cool the solution to 10°. Dissolve 17 8 g. of hydroxylammonium chloride or 21 g. of hydroxylammonium sulphate in 60 ml. of water, cool to 10°, and add 42 -5 ml. of QN sodium hydroxide solution if the resulting solution of tydroxylamine is not clear, filter it at the pump. Without delay add the hydroxylamine solution, with stirring, to the ammoniacal cupric sulphate solution. Reduction occurs at once, a gas is evolved, and the solution assumes a pale blue colour. Protect the reducing agent from the air if it is not used immediately. 

Cupric chloride or copper(II) chloride [7447-39 ], CUCI2, is usually prepared by dehydration of the dihydrate at 120°C. The anhydrous product is a dehquescent, monoclinic yellow crystal that forms the blue-green orthohombic, bipyramidal dihydrate in moist air. Both products are available commercially. The dihydrate can be prepared by reaction of copper carbonate, hydroxide, or oxide and hydrochloric acid followed by crystallization. The commercial preparation uses a tower packed with copper. An aqueous solution of copper(II) chloride is circulated through the tower and chlorine gas is sparged into the bottom of the tower to effect oxidation of the copper metal. Hydrochloric acid or hydrogen chloride is used to prevent hydrolysis of the copper(II) (11,12). Copper(II) chloride is very soluble in water and soluble in methanol, ethanol, and acetone. 

Materials. Monomers used in the preparation of the copolymers were as follows acrylamide as a 50% solution in water, stablized with cupric ion, supplied by American Cyanamid Company acrylic acid supplied by BASF and AMPS, 2-acrylamido-2-methylpropanesulfonic acid, (recrystallized grade) obtained from Lubrizol. The sodium salts of acrylic acid and AMPS were prepared by gradual neutralization of the monomers with sodium hydroxide solution, maintaining a temperature of 0 to 5°C, to give a final concentration of 50%. 

Other Methods of Preparation.—Ethyl 2-(D-ara6i no-tetrahydroxybutyl)-5-methyl-4-furoate has been prepared by heating D-glucose plus ethyl acetoacetate in aqueous alcohol without a catalyst,1 or from the same reagents (1 g. and 0.5 ml., respectively) in 0.5 ml. of 96% ethanol plus 1.5 ml. of water at room temperature in the presence of ferric chloride, zinc chloride (with small quantities of hydrochloric acid or of sodium hydroxide), cupric chloride, ferric sulfate, zinc sulfate, aluminum chloride, nickel chloride, or cobalt nitrate.18... 

Also, copper(lI) oxide may be prepared by adding alkab hydroxide to a cupric salt solution the bulky blue slurry of hydroxide obtained is then dehydrated by warming ... 

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