Copper-bismuth

Vacuum breaker with copper-bismuth contacts ... 

Low resistance-high kA alloy (high melting point) copper-bismuth has a good resistance to cold... 

Perhaps the most obvious metallic property is reflectivity or luster. With few exceptions (gold, copper, bismuth, manganese) all metals have a silvery white color which results from reflecting all frequencies of light. We have said previously that the electron configuration of a substance determines the way in which it interacts with light. Apparently the characteristic reflectivity of metals indicates that all metals have a special type of electron configuration in common. 

In a similar determination described by Lingane and Jones,11 an alloy containing copper, bismuth, lead, and tin is dissolved in hydrochloric acid as described above, and then 100 mL of sodium tartrate solution (0.1 M) is added, followed by sufficient sodium hydroxide solution (5M) to adjust the pH to 5.0. After the addition of hydrazinium chloride (4 g), the solution is warmed to 70 °C and then electrolysed. Copper is deposited at —0.3 volt, and then sequentially, bismuth at —0.4 volt, and lead at —0.6 volt all cathode potentials quoted are vs the S.C.E. After deposition of the lead, the solution is acidified with hydrochloric acid and the tin then deposited at a cathode potential of — 0.65 volt vs the S.C.E. 

In former times, tin was used widely as a constituent of metal alloys, of which bronze, solder, and pewter are common examples. Bronze is an alloy of copper containing approximately 20% tin and smaller amounts of zinc. Pewter is another Cu-Sn alloy that contains tin as the major component ( 85%), with roughly equal portions of copper, bismuth, and antimony. Solder consists of 67% lead and 33% tin. 

Selenium is extracted as diethyldithiocarbamate complex from the solution containing citrate and EDTA [5]. Ohta and Suzuki [6] found that only a few elements, such as copper, bismuth, arsenic, antimony, and tellurium, are also extracted together with selenium. They examined this for effects of hundredfold amounts of elements co-extracted with the selenium diethyldithiocarbamate complex. An appreciable improvement of interferences from diverse elements was observed in the presence of copper. Silver depressed the selenium absorption in the case of atomisation of diethyldithiocarbamate complex, but the interference of silver was suppressed in the presence of copper. The atomisation profile from diethyldithiocarbamate complex was identical with that from selenide. 

Rodionova and Ivanov [667] used chelate extraction in the determination of copper, bismuth, lead, cadmium, and zinc in seawater. The metal complexes of diethyl and dithiophosphates are extracted in carbon tetrachloride prior to determination by atomic absorption spectrometry. 

Tin and lead are the most rapid precipitants of metallic silver from the nitrate cadmium, zinc, copper, bismuth, and antimony axe moro slow in their operation, and mercury still more tardy. Chloride of silver is rapidly reduced by most of the metals which form soluble chlorides, such as zinc, iron, cadmium, cobalt, and arsenic. Zinc, copper, and arsenic rapidly reduce the ammoniacal solution of oxide of silver. Of all the metallic precipitants, zinc and cadmium are the most effective but when zinc or antimony aro used, the separated silver contains these metals. 

The use of sulphur dioxide as precipitant was first proposed by Berzelius, but accurate results by this method are only obtainable under special conditions. Complete precipitation does not take place from a strongly acid solution, and in the presence of other metals small amounts of these are liable to be carried down. In the presence of heavy metals such as copper, bismuth and antimony, the following procedure has been recommended 2 The tellurium is oxidised to telluric acid by the addition of ammonium perdisulphate in the presence of potassium hydroxide, excess of perdisulphate being subsequently removed by boiling. The heavy metals present are next removed by means of hydrogen sulphide. The tellurium may then readily be estimated by reduction with hydrogen chloride and precipitation with sulphurous acid. 

Salts of Copper, Bismuth, and Lead. — Dissolve 1 gm. of silver nitrate in 5 cc. of water, and add to the solution 10 cc. of ammonia water. The liquid should remain clear and colorless. 

Although this was a simple, relatively safe mixture, and was a satisfactory primer, it was discontinued after a very short period because of two major disadvantages. It was shown that copper, bismuth, silver, iron, and nickel increased the oxidation rate of red phosphorus to acidic compounds. Primer cups had to be zinc plated to prevent contact with copper. The red phosphorus had to be of high purity, and it was necessary to remove the major impurities (iron and copper) from commercial red phosphorus before use, and to coat the purified material with up to 7.5% aluminum hydroxide which inhibited oxidation. 

The Reppe process is used to make 1,4-1 butanediol from acetylene. In this process, acetylene and formaldehyde are reacted in the presence of a copper-bismuth catalyst. The resulting intermediate, 2-butyne-l,4-diol is hydrogenated over a Raney nickel catalyst ... 

In this paper. We report the hydrothermal synthesis, structural characterization and ionic conductivity of a novel hydrated copper bismuth vanadate, Cu2Bi4V20i3 3H20 and its high temperature phase. 

If two metals normally have similar discharge potentials, the conditions can be altered to make them sufficiently different for separation to be possible. For example, in the case of nickel and zinc in ammoniacal solution, to which reference was made previously, the deposition potentials are similar at 20 , but differ at 90 . The two metals can thus be separated satisfactorily at the higher temperature, but not at the lower. Another illustration is provided by the copper-bismuth system, in which simultaneous deposition takes place from simple salt solutions if cyanide is added, however, the copper ions form the complex cuprocyanide and the discharge potential becomes more negative (cf. Table LXXXIII). If citric or tartaric acid is present to keep the bismuth in solution, the addition of cyanide hardly affects the deposition potential of this metal quantitative separation from copper is then possible. 

Lingane and Jones devised an electrogravimetric procedure for the successive determinations of copper, bismuth, lead, and tin in the presence of various other metals. After each deposition the pH and electrode potential are adjusted, and the cathode is replaced in the solution for continued electrodeposition. 

Other examples of selective electrodeposition are given in books by Lingane, Diehl, and Sand. As examples may be cited the separation of silver from copper, bismuth from copper, antimony from tin, cadmium from zinc, and rhodium from iridium. 

Coulometric determinations of metals with a mercury cathode have been described by Lingane. From a tartrate solution, copper, bismuth, lead, and cadmium were successively removed by applying the appropriate cathode potential, which was selected to correspond to a region of diffusion-controlled current determined from current-voltage curves with a dropping mercury electrode. With a silver anode, iodide, bromide, and chloride can be deposited quantitatively as the silver salt. By controlling the anode potential, Lingane and Small determined iodide in the presence of bromide or chloride. The separation of bromide and chloride, however, was not successful because solid solutions were formed (Section 9-4). 

The solution of rare earth salts is saturated with hydrogen sulfide to remove lead, copper, bismuth, molybdenum, etc, and the rare earths precipitated by adding oxalic acid solution. Separation from the common elements is somewhat more effectively accomplished if both the solutions are boiling hot, the oxalic acid being added slowly while stirring. The crude oxalates are filtered and thoroughly washed. 

Separation.2- Uranium may be separated from copper, bismuth,arsenir, etc., by the fact that it is not precipitated from acid solution by 11 sS. Hie separation from lead i best accomplished by adding sulfuric acid to the nitrate solution and evaporating to fumes. 

Occurrence, — Selenium must be considered a rare element, although it is found widely distributed in nature. The distinctive selenium minerals are rare, and they are usually selenides, of such metals as lead, mercury, copper, bismuth, and silver. The element is also found in the free state associated with sulfur and as a selenite. The most common occurrence of selenium is in ores in which the element has partially displaced sulfur. Generally the selenium is present in very small proportions, but on account of the fact that enormous quantities of sulfide ores are used, this represents a considerable amount of selenium. It occurs also in small amounts in meteoric iron, in volcanic lavas, and in certain deposits of coal. Traces of selenium have been detected in rain and snow. Even though present in mineral ores in mere traces, it is readily concentrated either in the flue dusts or in the anode mud of the electrolytic refineries. Considerable quantities are known to exist in Hawaii, Japan,... 

Copper, bismuth, and silver. The major portion of these elements reports to the lead bullion, although minor trace levels, particularly of copper and bismuth, can be found in the slag. 

Composition.—Calcium and antimony with a littlo iron. and traces of copper, bismuth, zinc, magnesia, and sulphuric acid. 

Some of the earliest work utilizing polarography for water analysis was done by Heller and co-workers in 1935 (J9). They determined as little as 0.01 mg./liter of copper, bismuth, lead cadmium, and zinc polarographically after extraction with dithizone and carbon tetrachloride. This work also described conditions of extraction for minimizing interferences in certain cases. 

B Copper group Copper, bismuth, antimony, arsenic... 

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