Hydrated copper oxide

Synonyms cupric hydroxide copper hydrate hydrated copper oxide... 

Add in turn 55 g. of anhydrous sodium carbonate, 27 g. of powdered arsenious oxide and i g. of hydrated copper sulphate to 175 ml. of water in a 2 litre beaker, and heat the stirred mixture until an almost clear solution is obtained then immerse the stirred solution in ice-water, and cool it to 5°. 

In addition, with high solid content of the cooling water and at high flow velocities, severe corrosive conditions exist which continuously destroy surface films. Cathodic protection alone is not sufficient. Additional measures must be undertaken to promote the formation of a surface film. This is possible with iron anodes because the anodically produced hydrated iron oxide promotes surface film formation on copper. 

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. 

Typically the internals of the coil show pits and pinholes and may even perforate. Corrosion debris is evident, usually containing green hydrated copper carbonate (CuC03 nH20) and red cuprous oxide (Cu20). 

Problems with heating coils Internal coil corrosion Note corrosion debris is green hydrated copper carbonate Cu[11IC03 nH20 red cuprous oxide Cu20 /ntemal coil deposition Acid corrosion from soft water. Pinhole corrosion from 02 and C02. Erosion corrosion over 6 ft/s flow. Hard water scale from hard water. 

The copper compounds include Bordeaux mixture and the so-called fixed coppers including the copper oxides, copper oxychloride, copper oxychloride sulfate, and related materials. Bordeaux mixture, since its discovery about 70 years ago, has been the classic fungicide for the control of late blight and still is more widely used than any other single material. Certain of its qualities, particularly adhesiveness, remain unequaled by its commercial competitors, and it is cheap and effective. However, the inconvenience of preparing Bordeaux mixture, and the unreliable quality of hydrated lime available in most places, have tempted many growers to switch to other copper compounds or organics. 

A basic copper chlorate is formed when soln. of potassium chlorate acidified with sulphuric acid are electrolyzed with an alternating current between copper electrodes (L. Rossi) 83 when the hydrate is heated above 100° (A. Wachter) when a soln. of copper chlorate be mixed with pieces of marble or urea, and heated in a sealed tube to 130° (L. Bourgeois) when the hydroxides of the alkalies or alkaline earths act on cupric chlorate soln., or copper hydroxide acts on soln. of potassium chlorate (A. Brochet) when hydrated cupric oxide or cupric hydroxide acts on cupric chlorate soln. (P. Sabatier) or when potassium chlorate acts on cupric acetate soln. (A. Casselmann), basic cupric chlorate is obtained. The basic chlorate forms bluish-green monoclinic prisms of sp. gr. 3 55 and composition 4Cu0.C1205.3H20, that is, Cu(C103)2.3Cu(0H)2, which A. Werner considers to be hexahydroxyl cupric chlorate ... 

In the commoner cases the base is a hydrated metallic oxide (of aluminium, tin, lead, zinc or, less often, chromium, iron, copper, antimony) to which the colouring matter (if acid) is united by true chemical combination tannin lakes are also made (with basic colouring matters). In other lakes the base is an inert substance (barium sulphate, precipitated alumina and silica, chalk, gypsum, kaolin, etc.), on which the colouring matter is fixed by simple mechanical absorption. Lakes of the former kind may be mixed, either fraudulently or for the purpose of attenuating the colour, with inert materials. 

The hydroxides may also contain water of hydration additionally present may be some red-brown hematite (Fe2C>3), gray-black iron carbonate (FeCC>3), plus copper oxide, silicates, etc. 

Describe how you would prepare some crystals of hydrated copper(n) sulfate from copper(n) oxide and dilute sulfuric acid. Draw a diagram of the apparatus you would use and write a balanced chemical equation for the reaction. 

Oxidation.1 Hydrated copper permanganate oxidizes alcohols in CH2C12 rapidly and in high yields. Ketones are obtained from secondary alcohols, and carboxylic acids from primary and benzylic alcohols. Primary or secondary allylic alcohols are also oxidized efficiently. Anhydrous reagent is much less active. 

In the process of A. P. Browne2 a 10 per cent, solution of sodium nitrate is electrolysed in a wooden cell which is divided into two compartments. At the lead anode NO, ions attack the metal forming lead nitrate, and at the copper cathode caustic soda is produced. These electrolytically prepared solutions are drawn off when a suitable concentration is reached, and by mixing them, hydrated lead oxide is precipitated, which by subsequent treatment with sodium bicarbonate is converted into white lead. 

Summary Copper-II-oxide is formed in a similar manner as for iron-II-oxide. It is prepared, first, by electrolyzing a solution of pickling salt using copper electrodes. During the electrolysis process, a messy precipitate of mixed hydrated copper hydroxides are formed. Thereafter, this precipitate is collected by filtration, and then dried. The dry mass is then roasted at high temperature for several hours to facilitate formation of copper-II-oxide, which is formed by the dehydration and oxidization of the hydrated copper... 

Figure 062. Set-up for the preparation of mixed hydrated copper hydroxides (practically identical to the iron oxide...

To prepare copper-II-oxide, all you need to do is place the dried mass of hydrated copper hydroxides (prepared in step 1) into a crucible and then heat at 600 to 800 Celsius using a typical Bunsen burner for about 3 to 4 hours. During the heating process, water is volatized and removed, and the copper hydroxides are oxidized to copper-II-oxide forming a black powder. After the roasting process, the copper-II-oxide is cooled, and then stored in any suitable container. This copper-II-oxide can be used in pyrotechnic compositions, or used as a catalyst for the oxidation of various gases, such as the oxidation of methanol to formaldehyde. 

Reduction of colloidal copper oxide in concentrated solution by hydrazine hydrate produces the unstable, blue liquid hydrosol, but in dilute solution in presence of ammonia the product is a stable, red liquid hydrosol. Evaporation of the red solution in presence of hydrazine hydrate yields a stable, solid red hydrosol. Other colloidal forms of copper combined with sodium lysalbate or protalbate have been prepared.4... 

The presence of pyrites in mineral veins is frequently betrayed by the brown, rusty appearance of the upper parts of the deposits. This is well exemplified in the case of certain copper lodes, the iron of the contained copper pyrites having become converted into hydrated ferric oxide or rust. Such weathered zones are known as gozzans, and frequently present a cavernous or honeycombed appearance, due to the removal of pyritic material. In France the gozzan is termed the chapeau de fer, and in Germany der eiserne Hut, and an old adage states that4... 

The reaction of a strong solution of aqueous ammonia with the sulfide concentrate in a strongly agitated pressure vessel at a temperature between 160 and 190°F under an oxygen partial pressure of about 10 psi, either as pure oxygen or as compressed air, fulfills the optimal conditions for the above requirements. The iron present in the concentrate is oxidized to hydrated ferric oxide which, together with the silicates is insoluble in aqueous ammonia. The copper, nickel, and cobalt form their amines, while the sulfides are oxidized to sulfates, thiosulfates, and polythionates. 

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