Copper quantitative analysis

It is used in quantitative analysis as a reagent for copper and iron. 

When heated with pyrocatechol [720-80-9] copper powder, and alcohoHc sodium hydroxide, carbon tetrachloride gives a blue color that changes to red on addition of hydrochloric acid. This color reaction is not produced by chloroform. Quantitative analysis of carbon tetrachloride may be done by first decomposing the sample free of organic and inorganic chlorides, heating in a sealed tube with alcohoHc potash, and subsequently determining the potassium chloride formed as the silver haHde. The Zeiss interference refractometer has been used to determine the concentration of carbon tetrachloride vapor in air (36). 

In contrast to the well-established methods for identifying and quantifying naturally occurring chlorophylls, very few reports concern quantitative analysis of chlorophyllin copper complexes in color additives and in foodstuffs. Analytical methods proposed are based on spectral properties, elemental analysis, chromatographic separation, and molecular structure elucidation or a combination of these procedures. 

This discussion of EXAFS on ruthenium-copper clusters has emphasized qualitative aspects of the data analysis. A quantitative data analysis, yielding information on the various structural parameters of interest, has also been made and published (8). Of particular Interest was the finding that the average compo tion of the first coordination shell of ruthenium and copper atoms about a ruthenium atom was about 90% ruthenium, while that about a copper atom was about 50% ruthenium. Details of the methods Involved in the quantitative analysis of EXAFS data on bimetallic clusters can be obtained from our original papers (8.12-15). 

Quantitative analysis of the data revealed that the first coordination shell of the average Ru atom in the bimetallic catalyst contains 90% Ru and 10% Cu, whereas the first coordination shell of the average Cu atom contains 50% Cu and 50% Ru. This, together with the overall lower coordination of copper, is in agreement with particles consisting of an Ru core and an outer shell of Cu atoms. 

Elemental composition Cu 57.47%, C 5.43%, H 0.91%, 0 36.18%. Both malachite and azurite may be identified by x-ray analysis and analyzed qualitatively using physical properties such as refractive index and density. For quantitative analysis, the compound may he digested in nitric acid and analyzed for copper by various instrumental methods (see Copper.)... 

Brandt published a description of this mineral in the volume of the Acta of die Upsala Academy for 1742 and in Vetenskapsacademiens Handlingarna for 1746, and mentioned that it contains cobalt, iron, and sulfur, but that, unlike ordinary cobalt glance, it is free from arsenic. When W. von Hisinger made a quantitative analysis of it m 1810, he found it to be cobalt sulfide. This mineral is now known as linnaeite its formula is CosS4, in which part of the cobalt may be replaced by nickel, iron, or copper. 

Metals, especially copper, zinc and lead, may be found in spirits in small quantities derived from the distillation apparatus or the storage vessels. They are detected and determined by evaporating a sufficient quantity of the liquid, incinerating the residue and treating the ash by the ordinary methods of qualitative and quantitative analysis. 

The ash of true leather tanned with tannin consists essentially of calcium carbonate with traces of iron and of phosphates. Coloured leathers may contain metals from the mordants used (tin, copper, iron, chromium, aluminium) tin may also be introduced as stannous chloride used for bleaching. Small quantities of silicates (talc, kaolin) may be employed in the treatment of the leather. Finally, other mineral matters (barium, magnesium and lead salts and sodium chloride) may have been added as filling to increase the weight. Complete quantitative analysis of the ash is rarely necessary, but determination of its calcium content is sometimes required, this being made by the ordinary methods. 

Warren, H.V., Horksy, S J. and Gould, C.E. (1983) Quantitative analysis of zinc, copper, lead, molybdenum, bismuth, mercury and arsenic in brain and other tissues from multiple sclerosis and non-multiple sclerosis cases. Science of the Total Environment, 29(1-2), 163-69. 

Table I. Blue Copper Covalency - Quantitative Analysis of g Values...

British Standard 5666, Methods of Analysis of Wood Preservatives and Treated Timber, Part 3, Quantitative Analysis of Preservatives and Treated Timber Containing Copper, Chromium, Arsenic Formulations, British Standards Institution, 2 Park Street, London W1A 2BS, 1979. 

These reactions are used in quantitative analysis for the iodometric determination of copper. 

A variant of the same basic method is shown later in Fig. 3. In this case, a vacuum system is used for handling the gases, a large-bore stopcock is used in place of the flexible closure, and a different method is used for the quantitative analysis of CO2. Instead of absorbing the CO2 on Ascarite II, the CO2—Ar or CO2—He mixture is slowly pumped through a copper coU immersed in liquid nitrogen. The CO2 will be efficiently trapped, and after all the Ar or He has been removed, the trap is allowed to warm to room temperature and the CO2 pressure is determined. 

In the early 1950s there were proposed several procedures involving carboxylic acids for separation of metals such as copper and beryllium (9, 87, 140, 149). After these analytical applications of the carboxylate extraction system, Hok-Bemstrom published a series of papers dealing with the quantitative analysis of the extraction equilibria involving metal carboxylates (48-50). Since then the extraction of metal carboxylates has been extensively studied and the subject has been reviewed from time to time by the following authors Fletcher and Flett (23), Flett and Jaycock (26), Ashbrook (8), Miller (85), Rice (118), and Brzozka and Rozycki (14). Martinov has elaborated a data compilation... 

During the fifteenth century the metals zinc, antimony, bismuth, and probably cobalt were discovered, together with many new reactions now used in quantitative analysis. For example, A. Libavius (1540-1616) noted how ammonia in water could be determined by the blue color formed with a copper salt. Robert Boyle (1627-1691) was the first to use a solution of hydrogen sulfide (which he made from flowers of sulfur, potash, and ammonium chloride) as an analytical reagent, and he noted the black precipitate it formed with lead, gold, and mercury. 

This reaction occurs because of the extraordinary stability of cuprous iodide, which is discussed in the following section. The reaction is used in a method of quantitative analysis for copper, the liberated iodine being determined by titration with sodium thiosulfate solution. 

Tetramethylthiuram disulfide (thiram) (38) (R = Me) forms insoluble chelates, with certain metals, e.g. copper and zinc. This reaction is extensively used for the detection and quantitative analysis of heavy metals. Thiram forms both 1 1 and 1 2 metal chelates (Scheme 19). 

The technique involves the use of an inductively coupled plasma to convert trace elements to their gaseous ions followed by analysis of these ions by mass spectrometry. Examples include the quantitative analysis of trace copper by isotope dilution and the analysis of trace contaminants in boron, indium phosphide and reagent acids. 

The reaction which occurs when copper sulfate solution is added to protein dissolved in alkali has been used for quantitative analysis for more than 50 years (R12). According to Mehl et al. (M17), the blue-violet product is a copper complex in which each Cu atom is bound to four peptide N atoms it has an at 552 nm. 

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