Copper solution

B) Preparation of the Cuprous Solution, Add 85 ml. of concentrated ammonia solution (d, o-o88) to a solution of 50 g. of crystalline copper sulphate in 200 ml. of water, and cool to 10 . Dissolve 14 5 g. of hydroxylamine hydrochloride (or 17-4 g. of the sulphate) in 50 ml. of water, cool to 10 , and add a solution of 9 g. of sodium hydroxide in 30 ml. of water. Without delay add this hydroxylamine solution with stirring to the copper solution, which will be immediately reduced, but will retain a blue colour. 

Acetylene has a low solubiHty in Hquid oxygen. Excessive concentrations can lead to separation of soHd acetylene and produce accumulations that, once initiated, can decompose violently, detonating other oxidizable materials. Acetylene is monitored routinely when individual hydrocarbons are determined by gas chromatography, but one of the wet classical methods may be more convenient. These use the unique reaction of acetylene with Ilosvay s reagent (monovalent copper solution). The resulting brick-red copper acetyHde may be estimated colorimetricaHy or volumetricaHy with good sensitivity (30). 

Electrowinning. Vat leaching often yields copper solutions having concentrations sufficiently high for direct electrowinning. However, high concentrations of cations other than copper and low copper concentrations make it more difficult to obtain high purity electrolytic copper by direct electrolysis of leach solutions than by electrolysis of purified solutions obtained from solvent extraction. 

Electroless copper solutions underwent similar development during the same period (10). Early printed circuit boards used mechanically attached eyelets to provide electrical conductivity between the copper sheathing laminated on two sides of a plastic board. Electroless copper plating provided a less expensive, better conductive path, allowing much greater numbers and smaller sizes of holes. Later, electroless coppers even replaced the laminated bulk copper sheathing in the semiadditive and additive processes (see Copper). 

Process Control. Some hot nickel and flash electroless copper solutions are plated to the point of exhaustion and then discarded. Most baths are formulated to give bath fives of >6 turnovers of the bath constituents some reach steady-state buildup of the by-products and can be used indefinitely. AU. regenerable solutions should be filtered to remove particulates that can cause deposit roughness and bath instability. 

Copper anodes for use in acid copper plating solutions preferably contain a small amount of phosphoms [7723-14-0] usually 0.03—0.04 wt %, which retards chemical dissolution of the copper and thus the subsequent copper build-up. Typically, acid copper plating solutions increase in copper and require periodic dilution. Additionally, additives for brightening acid copper baths tend to last longer in plating tanks using phosphorized copper anodes. In cyanide copper solutions, phosphorized copper anodes should not be used. 

Some metals are soluble as atomic species in molten silicates, the most quantitative studies having been made with Ca0-Si02-Al203(37, 26, 27 mole per cent respectively). The results at 1800 K gave solubilities of 0.055, 0.16, 0.001 and 0.101 for the pure metals Cu, Ag, Au and Pb. When these metal solubilities were compared for metal alloys which produced 1 mm Hg pressure of each of these elements at this temperature, it was found drat the solubility decreases as the atomic radius increases, i.e. when die difference in vapour pressure of die pure metals is removed by alloy formation. If the solution was subjected to a temperature cycle of about 20 K around the control temperamre, the copper solution precipitated copper particles which grew with time. Thus the liquid metal drops, once precipitated, remained stable thereafter. 

Thorough rinsing between the pretreatment steps is essential to prevent carry-over of solutions. The commonest plastic plated is ABS (acrylonitrile butadiene styrene copolymer) but procedures are also available for polypropylene and other plastics. In some proprietary processes, electroless copper solutions are used to give the initial thin conducting layer. 

Pipette 25 mL of the copper solution (0.01 M) into a conical flask, add 100 mL de-ionised water, 5 mL concentrated ammonia solution and 5 drops of the indicator solution. Titrate with standard EDTA solution (0.01 M) until the colour changes from purple to dark green. 

Construct a calibration curve using the synthetic standard solution add the standard copper solution immediately before the reagent. 

Discussion. The titration of a copper ion solution with EDTA may be carried out photometrically at a wavelength of 745 nm. At this wavelength the copper-EDTA complex has a considerably greater molar absorption coefficient than the copper solution alone. The pH of the solution should be about 2.4. 

The present description pertaining to copper refers to solvent extraction of copper at the Bluebird Mine, Miami. When the plant became operational in the first quarter of 1968 it used L1X 64, but L1X 64N was introduced in to its operation from late 1968. The ore consists of the oxidized minerals, chrysocolla and lesser amounts of azurite and malachite. A heap leaching process is adopted for this copper resource. Heap-leached copper solution is subjected to solvent extraction operation, the extractant being a solution of 7-8% L1X 64N incorporated in kerosene diluent. The extraction process flowsheet is shown in Figure 5.20. The extraction equilibrium diagram portrayed in Figure 5.21 (A) shows the condi-... 

The design and capacity of an RO unit is dependent upon the type of chemicals in the plating solution and the dragout solution rate. Certain chemicals require specific membranes. For instance, polyamide membranes work best on zinc chloride and nickel baths, and polyether/amide membranes are suggested for chromic acid and acid copper solutions. The flow rate across the membrane is very important. It should be set at a rate to obtain maximum product recovery. RO systems have a 95% recovery rate with some materials and with optimum membrane selection.22... 

Table 9.5 Effect of ultrasound on the turbidity and conductance of different copper solutions...

Turanose Phenylosotriazole. A solution of 15 g. of turanose phenylosazone in 300 cc. of hot water was placed on the steam-bath and a solution of 22 g. of copper siilfate pentahydrate in 150 cc. of hot water was added. The mixture turned a deep cherry-red at once and in a short time (fifteen min.) a red precipitate had formed and the solution had become green. After thirty minutes from the time of addition of the copper solution, the solution was cooled, filtered, and the copper removed as sulfide. The clear light yellow filtrate was neutralized with 45 g. of barium carbonate and the insoluble material removed by filtration. The filtrate was extracted with five 50-cc. portions of ether to remove the aniline, and the aqueous portion was concentrated in vacuo to a thick sirup. The sirup was dissolved in 60 cc. of warm alcohol, filtered to remove a slight turbidity and diluted with 65 cc. of ether. Upon cooling and scratching, the product crystallized as large prisms yield 8.9 g. (72%). The phenylosotriazole was recrystallized from 10 parts of alcohol and when pure showed the melting point 193-194° and rotated [a Jj" + 74.5° in aqueous solution (c, 0.90). 

The tetrahydroxybutylpyrrole derivatives reduce alkaline copper solution somewhat, the reduction being more intense when the compounds are previously heated with an alkali. Since this property is displayed even when the compound has no carbonyl group, it cannot be attributed to the functional groups of the compound. It can better be explained by the possibility that the alkali ruptures the chain, with the formation of reducing sub-... 

Loss of copper. Solutions and crystals of ceruloplasmin that have been allowed to stand for several weeks partially lose their blue color and this may indicate changes in copper oxidation state and/or loss of copper. A series of experiments are required to determine whether any copper loss is site preferential and how this is affected by anionic inhibitors. 

Tsai, C.F. 1979. Survival, overturning and lethal exposure times for the pearl dace, Semotilus margaritus (Cope), exposed to copper solution. Comp. Biochem. Physiol. 64C l-6. 

Zn Zn2+ Cu2+ Cu. This battery comprised two concentric terracotta pots, the outer pot containing a zinc solution and the inner pot containing a copper solution. Metallic rods of copper and... 

Tell how you would prepare 500 mL of a 25 ppm copper solution from pure copper metal. Solution 5.8... 

A series of five standard copper solutions are prepared, and the absorbances are measured as indicated below. Plot the data and determine the concentration of the unknown. 

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