Copper hydrate

Synonyms cupric hydroxide copper hydrate hydrated copper oxide... 

Add copper sulphate solution and then excess caustic soda solution. Solution turns violet, but precipitation of copper hydrate does not take place. On warming, reduction of the cupric compound occurs and red cuprous oxide is precipitated (Trammer s test). 

Synonyms Bis(1,1,1,6,6,6-hexafluoro pentane-2,4-dionato)copper hydrate Cu(hfa)2H20... 

Synonyms Copper dihydroxide Copper hydrate Copper (II) hydroxide Copper (2+) hydroxide Copper oxide hydrated Cupric hydroxide... 

Dr, Muter 8 Method —This method may be used for the determination of glycerin in soap and soap leys, the process being based on the power of glycerin to arrest the precipitation of copper hydrate by the alkalies. The procedure is as follows —... 

Add 60 c.c. of a strong solution of potassium hydrate (1 in 2) and then a weak solution of sulphate of copper, very gradually, and with constant shaking, until a fair amount of copper hydrate is produced which remains undissolved make the whole up into a given hulk, close the tube, and set aside to settle. 

Church (1901) lists this as a new addition. It was said to be an artificial copper hydrate, friough the precise composition is unknown. 

Cupric oxide or black copper oxide.) CuO. Mol. wt. 79.54 sp. gr. 6.4 decomposes at 1026°C. Insoluble in water and soluble in acids and NH4CI. Derived by the ignition of copper carbonate or copper nitrate, copper hydrate, or oxidation of lower oxides. 

Dichloroethanoic acid, CHCljCOOH. Low-melting solid, m.p. 5-6 "C, b.p. 194°C. Prepared by the action of copper powder on trichloroethanoic acid or by the action of sodium cyanide on chloral hydrate. 

Sulphur dichloride oxide (thionyl chloride) on the hydrated chloride can also be used to produce the anhydrous chloride in certain cases, for example copper(II) chloride and chromium(III) chloride ... 

The anhydrous chloride is prepared by standard methods. It is readily soluble in water to give a blue-green solution from which the blue hydrated salt CuClj. 2H2O can be crystallised here, two water molecules replace two of the planar chlorine ligands in the structure given above. Addition of dilute hydrochloric acid to copper(II) hydroxide or carbonate also gives a blue-green solution of the chloride CuClj but addition of concentrated hydrochloric acid (or any source of chloride ion) produces a yellow solution due to formation of chloro-copper(ll) complexes (see below). 

Hydrated copper(ll) hydroxide, Cu(OH)2, is precipitated as a pale blue solid when alkali is added to an aqueous solution of a copper(II) salt ... 

Addition of water gives the hydrated nitrate Cu(N03)2.3H2O, the product obtained when copper (or the +2 oxide or carbonate) is dissolved in nitric acid. Attempts to dehydrate the hydrated nitrate, for example by gently heating in vacuo, yield a basic nitrate, not the anhydrous salt. 

The solid readily dissolves chemically in concentrated hydrochloric acid, forming a complex, and in ammonia as the colourless, linear, complex cation [H3N -> Cu <- NHj] (cf AgCl) if air is absent (in the presence of air, this is oxidis to a blue ammino-copper(II) complex). This solution of ammoniacal copper(I) chloride is a good solvent or carbon monoxide, forming an addition compound CuCl. CO. H2O, and as such is used in gas analysis. On passing ethyne through the ammoniacal solution, a red-brown precipitate of hydrated copper(I) dicarbide (explosive when dry) is obtained ... 

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°. 

We may now understand the nature of the change which occurs when an anhydrous salt, say copper sulphate, is shaken with a wet organic solvent, such as benzene, at about 25°. The water will first combine to form the monohydrate in accordance with equation (i), and, provided suflScient anhydrous copper sulphate is employed, the effective concentration of water in the solvent is reduced to a value equivalent to about 1 mm. of ordinary water vapour. The complete removal of water is impossible indeed, the equilibrium vapour pressures of the least hydrated tem may be taken as a rough measure of the relative efficiencies of such drying agents. If the water present is more than sufficient to convert the anhydrous copper sulphate into the monohydrate, then reaction (i) will be followed by reaction (ii), i.e., the trihydrate will be formed the water vapour then remaining will be equivalent to about 6 mm. of ordinary water vapour. Thus the monohydrate is far less effective than the anhydrous compound for the removal of water. 

Cuprous chloride. Hydrated copper sulphate (125 g.) and sodium chloride (32-5 g.) are dissolved in water (400 ml.) boiling may be necessary. An allialine solution of sodium sulphite (from 26 5 g. of sodium bisulphite and 17 -5 g. of sodium hydroxide in 200 ml. of water) or the solution of the sodium bisulphite alone is added to the resulting hot solution during about 5 minutes with constant shaking. The solution will be decolourised or nearly so. It is then cooled to room temperature (or in an ice bath), and the supernatant liquid is decanted... 

Anhydrous sodium sulphide. The hydrated salt, NajS.QH O, is heated in a Pyrex distilling flask or retort in a stream of hydrogen or of nitrogen until water ceases to be evolved. The solid cake of anhydrous sodium sulphide is removed from the vessel with the aid of a copper wire hook or by other suitable means. No attempt should be made to fuse the sodium sulphide since at high temperatiues sodium sulphide is readily oxidised to sodium sulphate. 

Also the arene-arene interactions, as encountered in Chapter 3, are partly due to hydrophobic effects, which can be ranked among enforced hydrophobic interactions. Simultaneous coordination of an aromatic oc amino acid ligand and the dienophile to the central copper(II) ion offers the possibility of a reduction of the number of water molecules involved in hydrophobic hydration, leading to a strengthening of the arene-arene interaction. Hence, hydrophobic effects can have a beneficial influence on the enantioselectivity of organic reactions. This effect is anticipated to extend well beyond the Diels-Alder reaction. 

Use of Centered Period. A centered period is used to denote water of hydration, other solvates, and addition compounds for example, CUSO4 SHjO, copper(II) sulfate 5-water (or pen-tahydrate). 

Valentinite, see Antimony(III) oxide Verdigris, see Copper acetate hydrate Vermillion, see Mercury(II) sulflde Villiaumite, see Sodium fluoride Vitamin B3, see Calcium (+)pantothenate Washing soda, see Sodium carbonate 10-water Whitlockite, see Calcium phosphate Willemite, see Zinc silicate(4—)... 

Because huge quantities of by-product acetonitrile are generated by ammoxidation of propylene, the nitrile may be a low cost raw material for acetamide production. Copper-cataly2ed hydration gives conversions up to 83% (11), and certain bacteria can effect the same reaction at near room temperature (12). 

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