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Copper turnings

Traces of bromine, carried over with the gas, are removed by the copper turnings as black copper bromide if the level of the blackened copper in tube F rises appreciably, excessive amounts of bromine are being carried over. [Pg.182]

A solution of cuprous bromide may be prepared either by dissolving the solid in hot constant boiling point hydrobromic acid or by refluxing a mixture of 63 g. of crystallised copper sulphate, 20 g. of copper turnings, 154 g. of sodium bromide dihydrate, 30 g. (16-3 ml.) of concentrated sulphuric acid and 1 litre of water for 3-4 hours. If the colour of the solution has not become yellowish after this period of heating, a few grams of sodium sulphite should be added to complete the reduction. [Pg.191]

Qualitative Analysis. Nitric acid may be detected by the classical brown-ring test, the copper-turnings test, the reduction of nitrate to ammonia by active metal or alloy, or the nitrogen precipitation test. Nitrous acid or nitrites interfere with most of these tests, but such interference may be eliminated by acidifying with sulfuric acid, adding ammonium sulfate crystals, and evaporating to alow volume. [Pg.46]

Austenitic stainless steels-determination of resistance to intergranular corrosion. Part 1 Corrosion test in nitric acid medium by measurement of loss of mass (Huey test) Austenitic stainless steels-determination of resistance to intergranular corrosion. Part 2 Corrosion test in a sulphuric acid/copper sulphate medium in the presence of copper turnings (Moneypenny Strauss test)... [Pg.1103]

An elegant extension of these intramolecular acylnitrene-induced ring expansions has been used for the synthesis of cyclopent[h]azepines.2 2-Haloindan-l-yl azidoformates 14 (X = Cl, Br), when subjected to pyrolysis at 300 °C in a hot tube packed with calcium oxide and copper turnings, produce cyclopent[6]azepine (15), as a dark turquoise oil, in excellent yield. Lesser yields (30 and 50%, respectively) of the 4-bromo and 3-methoxy derivatives can be similarly obtained. [Pg.141]

Method 1. Prepare a solution of cuprous bromide by refluxing 31-5 g. of crystallised copper sulphate, 10 g. of clean copper turnings, 77 g. of crystallised sodium bromide, 15 g. (8-2 ml.) of concentrated sulphuric acid and 500 ml. of water contained in a 2 5 litre round-bottomed flask over a flame for 3-4 hoims until the solution acquires a yellowish colour if the blue coloim is not discharged, add a few grams of sodium bisulphite to complete the reduction. [Pg.602]

Catarole Also spelled Catarol. A process for making aromatic hydrocarbons and olefins by cracking petroleum fractions over copper turnings. Invented by C. Weizmann in England in... [Pg.54]

Nitric oxide also can be made by reactions of nitric acid, nitrate, or nitrite salts with metals, metal oxides, or sulfates. Several metals react with nitric acid liberating nitric oxide. (See Nitric Acid, Reactions). For example, action of 1 1 nitric acid on copper turnings forms nitric oxide ... [Pg.642]

The cuprous chloride solution prepared as described above is more satisfactory and cheaper than one prepared by reducing cupric chloride with copper turnings. [Pg.34]

Emission spectroscopy utilizes the characteristic line emission from atoms as their electrons drop from the excited to the ground state. The earliest version of emission spectroscopy as applied to chemistry was the flame test, where samples of elements placed in a Bunsen burner will change the flame to different colors (sodium turns the flame yellow calcium turns it red, copper turns it green). The modem version of emission spectroscopy for the chemistry laboratory is ICP-AES. In this technique rocks are dissolved in acid or vaporized with a laser, and the sample liquid or gas is mixed with argon gas and turned into a plasma (ionized gas) by a radio frequency generator. The excited atoms in the plasma emit characteristic energies that are measured either sequentially with a monochromator and photomultiplier tube, or simultaneously with a polychrometer. The technique can analyze 60 elements in minutes. [Pg.525]

In the LaMar Fluorination process [11] (referred to as LaMar in the following discussion) the substrates are condensed at low temperature into a tube packed with copper turnings through which fluorine, initially highly diluted in either helium or nitrogen, is passed. The concentration of fluorine and the reaction temperature are slowly increased over a period of several days to permit perfluorination. This is a batch process that requires relatively long reaction times to perfluorinate samples of material. [Pg.6]

Gases For nitrogen end argon passage through purification trass such os Mg(CIOt)i ond molecular sieve to remove water, CO. ond hydrocarbons then deexygenate in c furnace ot 623 K w th copper turnings... [Pg.66]


See other pages where Copper turnings is mentioned: [Pg.180]    [Pg.181]    [Pg.182]    [Pg.759]    [Pg.67]    [Pg.216]    [Pg.277]    [Pg.46]    [Pg.149]    [Pg.156]    [Pg.239]    [Pg.485]    [Pg.98]    [Pg.165]    [Pg.265]    [Pg.132]    [Pg.141]    [Pg.61]    [Pg.180]    [Pg.181]    [Pg.759]    [Pg.119]    [Pg.122]    [Pg.87]    [Pg.67]    [Pg.499]    [Pg.129]    [Pg.136]    [Pg.216]    [Pg.441]    [Pg.192]    [Pg.129]    [Pg.136]    [Pg.216]   
See also in sourсe #XX -- [ Pg.5 , Pg.21 ]

See also in sourсe #XX -- [ Pg.6 , Pg.21 ]

See also in sourсe #XX -- [ Pg.21 ]

See also in sourсe #XX -- [ Pg.5 , Pg.21 ]

See also in sourсe #XX -- [ Pg.6 , Pg.21 ]

See also in sourсe #XX -- [ Pg.267 ]




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