Cuprous Hydroxide

Kupfer-hammerschlag, m. copper scale, -hoch-ofen, m. copper blast furnace, -hiitte,/. copper smeltery, -hydrat, n. copper hydroxide, -hydroxyd, n. copper hydroxide, specif, cupric hydroxide, copper(II) hydroxide, -hydroxy-dul, n. cuprous hydroxide, copper(I) hydroxide. 

Kupferozydul, n. cuprous oxide, copper(I) oxide, -hydrat, n. cuprous hydroxide, cop-per(I) hydroxide, -salz, n. cuprous salt, copper (I) salt, -verblndung,/. cuprous compound, copper(I) compound. 

A. Preparation of Cuprous Hydroxide.—Cuprous chloride is prepared from a solution of 500 g. (2 moles) of crystallized copper sulfate and 150 g. (2.55 moles) of sodium chloride in 2.5 1. of water (Org. Syn. 3, 33) by the gradual addition of sodium sulfite (from no g. of sodium bisullite). After decanting the supernatant solution, the precipitate of cuprous chloride is added to a solution of 350 cc. of 6 N sodium hydroxide in r 1. of water contained in the 4-I. beaker in which the main synthesis is to be performed, the last portion of solid cuprous chloride being washed in with 1 1. of water. After vigorously stirring for a few minutes, the heavy precipitate of deep orange-colored cuprous hydroxide is permitted to settle and the supernatant... 

Cuprous cyanide, 4, 69 Cuprous Hydroxide, 7, 30 Cuprous oxide, 6, 6 7, 33 Cyanoacetic acid, 7, 22 Cyanoacetic ester (ethyl), 7, 21 Cyanohydrin Synthesis, 6, 58 a-CYANO-/3-PlIENYLACRYLIC ACID, 7, 20, 21... 

The general utility of this process was outlined by R. Lorenz1 in 1896. He employed a bath of alkali chloride, nitrate or sulphate, with a platinum cathode and an anode of that metal, the hydroxide of which was to be precipitated. This investigation established the following facts In potassium chloride solution, a copper anode gives yellowish cuprous hydroxide, whilst in a potassium nitrate solution... 

Cuprous hydroxide, CuOH.—The formation of the hydroxide by the interaction of alkalies and solutions of cuprous chloride has been described,7 but it is doubtful whether a definite compound has ever been isolated. 

The solubility products of cupric and cuprous hydroxides, Cu(OH)2 and CuOH, respectively, arc approximately 10 and 10 at ordinary temperatures [Allmand, J, Chem, Soc., 95, 2151 (1909)] show that the solid cupric hydroxide is unstable in contact with metallic copper and tends to be reduced to cuprous hydroxide. 

Preparation. The reagent is prepared by the reaction of acetylacetone with an ammoniacal solution of cuprous hydroxide. 

Dinitro-1,1 -azonaphthalene yel-brn ndls (from nitrobenz) om-yell ndls (by subln), mp 322-3° (Ref 3) 280° (from toluene) (Ref 6y, sparingly sol in boiling ale, glacial acetic acid or beh the color in coned HaS04 soln was reddish-violet, which changed to yel on heating. It was prepd by the reaction of 5-nitro-l-naphthalenediazonium sulfate with cuprous hydroxide (Refs 3 6)... 

In one such method (details of which are found on the Evolve site that accompanies this book), using Benedict s reagent (cupric ion complexed to citrate in alkaline solution), reducing substances convert cupric to cuprous ions, forming yellow cuprous hydroxide or red cuprous oxide. 

It forms large, colorless, efflorescent prisms fuses at 45° (113° F.) very soluble in HjO insoluble in alcohol. Its solutions precipitate alumina from solutions of A1 salts, without precipitating-Fe or Mn they dissolve many compounds insoluble in HsO cuprous hydroxid, iodids of Pb, Ag and Hg, sulfids of Ca and Pb. It acts as a disinfectant and antiseptic. HjSOa and most other acids decompose NaaSaOs according to the equation NaaSaOa-)-HaSOi = NaaS04-l-S0a-(-S- - HaO. Oxalic, and a few other acids, decompose the thiosulfate with formation of HaS as well as SOa and S. 

Hydroxids.— Cuprous Hydroxid — (Cn)3H303( ) —160.4 ( ) — is formed as a ymllow or red powder when mixed solutions of GuSO and KHO are heated in presence of glucose. By boiling the solution it is rapidly dehydrated with formation of (Cu,)0. 

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. 

A Yellow or white residues on copper surface. YeUow residue is usuaUy cuprous hydroxide. It is water insoluble and is left when boards are etched and alkah-cleaned. A white pre-dpitate wUl probably be cuprous chloride, which can remain after etching in solutions that are low in chloride ion and add. To eliminate both conditions, the solution in which the board is rinsed just before final water-spray rinsing should be 5 percent by volume hydrochloric acid. 

A test for the presence of reducing substances in urine. Benedict s reagent contains cupric ion complexed with citrate in alkaline solution. Glucose or other reducing substances reduce cupric ion to cuprous ion, resulting in the formation of yellow cuprous hydroxide or red cuprous oxide depending on the amount of reducing substance present. 

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