Ammoniacal cupric hydroxide

If ammoniacal cupric hydroxide is added to potassium ferricyamde the pent-ammoniate, Cu3[Fe(CN)6]2.5NH3J is obtained as black, stable crystals.1 The salt Cu3[Fe(CN)6]2.16NH3 has also been obtained.2... 

The aminocellulose powder is initially dissolved in ammoniacal cupric hydroxide and reprecipitated to produce a flocculent suspension. In this form it is converted to the diazonium derivative with nitrous acid and immediately allowed to react with protein. The following quantities are adequate for the binding of up to 500 mg of protein assuming a molecular weight of the protein of approximately 100,000. For small polypeptides (molecular weight in the region of 10,000 or less) these quantities would only be sufficient to react with 50 mg of peptide. 

In another process, cellulose is dissolved in ammoniacal cupric hydroxide (Cu(NH3>4(OH)2). The solution is then spun as a fiber into a dilute sulfuric acid solution to regenerate the cellulose. The product is called Cuprammonium rayon. The material may still be manufactured on a limited scale. 

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. 

Kupferoxyd, n. cupric oxide, copper(II) oxide, -ammoniak, n. ammoniacal copper oxide, cu-prammonium. -ammoniakkunstseide, -am-moniakzellulose, /. cuprammonium rayon, -hydrat, n. cupric hydroxide, copper(II) hydroxide. -salz, n. cupric salt, copper(II) salt. 

Schweitzer s reagent chem An ammoniacal solution of cupric hydroxide used to dissolve cellulose, silk, and linen, and to test for wool. shvTt-sorz re,a- 3nt scopoline orgchem CgHijOjH A white crystalline alkaloid that melts at 108-109°C, soluble in water and ethanol used in medicine. Also known as oscine. sko-p3,len ... 

C. Preparation of the reducing agent. One hundred and twenty-five grams (0.5 mole) of cupric sulfate pentahydrate is dissolved in 500 ml. of water contained in a 3-1. three-necked flask equipped with a mechanical stirrer, and then 210 ml. of concentrated ammonium hydroxide (sp. gr. 0.90) is added with stirring. The solution is cooled to 10°. A solution of 40 g. (0.575 mole) of hydroxylamine hydrochloride in 140 ml. of water is prepared and also cooled to 10°. To the hydroxylamine hydrochloride solution there is added 95 ml. of 6 A sodium hydroxide solution, and if not entirely clear, it is filtered by suction. This hydroxylamine solution is immediately added to the ammoniacal cupric sulfate solution with stirring. Reduction occurs at once with the evolution of nitrogen, and the solution becomes pale blue. If this solution is not used at once, it should be protected from the air. 

Cuprous sulphate dissolves in concentrated hydrochloric acid and in concentrated ammonium hydroxide. The ammoniacal solution yields a colourless, crystalline compound, Cu2S04,4NH3,H20, decomposed by water into metallic copper and an ammoniacal cupric compound.1 Cuprous sulphate is also dissolved to a slight extent by glacial acetic acid. The deep-violet solution thus produced is rapidly oxidized by air to a blue liquid, from which crystals of an acid cupric acetate are deposited.2... 

A second process for producing regenerated cellulose fibre was introduced in 1897 in Germany. In this method, cellulose is treated with an ammoniacal solution of cupric hydroxide (Cu(NH3)4(OH)2) to form a soluble complex. The solution is then spun into dilute sulphuric acid to regenerate the cellulose. This process is relatively expensive because of the need to recover copper. However, the product, called cuprammonium rayon, is still made on a limited scale because of its pleasing appearance and feel. 

Another typical property of cellulose and its derivatives dependent on water sorption is the swelling of the fibre that occurs under the influence of certain solutions such as aqueous sodium hydroxide or an ammoniacal solution of cupric oxide, i.e. cuprammonium . The process of swelling does not start with sorption as in the instance of water. In the first stage of swelling the liquid penetrates the molecular chains of the cellulose, gradually coming in contact with all of them so that chemical combination takes place to form alkali celluloses, (C6H,0O5) NaOH and (C6H,0O5)2 NaOH. 

On adding a solution of a ferrous salt to an ammoniacal solution of a cupric salt, ferric hydroxide is precipitated, the cupric salt being reduced to cuprous and remaining in solution. This affords a convenient... 

Ammonia water. See Ammonium hydroxide Ammonia white acid. See Ammonium bifluoride Ammonio-cupric sulfate. See Ammoniacal copper sulfate... 

Cupric oxide, ammoniacal Schweitzer s reagent (dissolves cotton, linen, and silk, but not wool). Dissolve 5 g of cupric sulfate in 100 mL of boiling water, and add sodium hydroxide until precipitation is complete. Wash the precipitate well, and dissolve it in a minimal quantity of ammonium hydroxide. Bubble a slow stream of air through 300 mL of concentrated ammonium hydroxide solution containing 50 g of fine copper turnings. Continue stirring for 1 hour. 

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