Sulphates pure metals

Manganese is the third most abundant transition metal, and is widely distributed in the earth s crust. The most important ore is pyrolusite, manganese(IV) oxide. Reduction of this ore by heating with aluminium gives an explosive reaction, and the oxide Mn304 must be used to obtain the metal. The latter is purified by distillation in vacuo just above its melting point (1517 K) the pure metal can also he obtained by electrolysis of aqueous manganese(II) sulphate. 

Nickel may also be prepared by electrolysis of ammoniacal, acidified, or neutral solutions of its salts, a process that is used commercially for electroplating.5 It is precipitated by zinc from ammoniacal solutions of its salts, and is left as a residue on igniting either the oxalate or the double nickel ammonium oxalate. Solutions of nickel salts are reduced by hydrogen when heated under pressure, metallic nickel being precipitated out of solution.7 Thus a N/5 solution of nickel sulphate deposits metallic nickel at 186° C. in the presence of hydrogen at 100 atmospheres pressure, whilst a similar concentration of nickel acetate deposits a pure nickel under like conditions at 168° C. 

Jumau s process (ut supra) for the electrolytic extraction of copper from its ores is also applicable to the production of pure copper from solutions of its compounds.8 The cupric sulphite or cupro-cupric sulphite precipitated from the copper solution by the action of sulphurous acid or a sulphide is decomposed by sulphuric acid into cupric sulphate and metallic copper. The metal thus liberated is pressed into a form suitable for an anode, and refined electrolytically. 

The salt obtained in this way is not pure, but contains small quantities of ferric sulphate and the sulphates of metals such as manganese naturally occurring in the pyrites. Copper sulphate is removed by allowing the liquors to remain a sufficient length of time m contact with the scrap iron, the copper being precipitated out —... 

The materials were prepared from silica free deionised water (0.1 mol L ) to which the compounds of interest were added in the form of acidic aqueous solutions. Sulphate, phosphate and chloride were added as ammonium salts, Al, Ca, Fe, K, Mg and Na as nitrates whereas the solution of Mn was obtained by dissolution of the pure metal in nitric acid. The concentrations expected upon spiking are given in Table 8.1. 

SUver is a white metal very malleable and ductile the best known conductor of heat and electricity. It is not acted on by pure air, but is blackened in air containing a tx e of H,S. It combines directly with d, Br, 1, S, P, and Aa. Hot H,SO, diaaolves it as sulphate, and BCNO, aa nitrate. caustic alkalies do not affect it. It alloys readily with many metals its allov with Cu is harder than the pure metal. 

Pure tin is completely resistant to distilled water, hot or cold. Local corrosion occurs in salt solutions which do not form insoluble compounds with stannous ions (e.g. chloride, bromide, sulphate, nitrate) but is unlikely in solutions giving stable precipitates (e.g. borate, mono-hydrogen phosphate, bicarbonate, iodide) . In all solutions, oxide film growth occurs and the potential of the metal rises. Any local dissolution may not begin for several days but, once it has begun, it will continue, its presence being manifested... 

Anhydrous Ethyl Ether. This is for those formulas calling for dry, pure, or anhydrous ether. The ether product from above is dried over thin slices of metallic sodium (metallic sodium wire works well also) for 24 hours. Then the ether is distilled on a water bath, over fresh (fresh means a different batch than what you used to dry with) metallic sodium. Note Ether develops explosive peroxides upon sitting for any length of time, even if just purchased from a supply house. Therefore, before handling ether, which has been stored, shake with ferrous sulphate or with lead peroxide. To keep peroxides from forming in fresh ether add several sections of copper or iron wire to the dark container and store in a cool place. 

According to F. C. Franklin and C. A. Kraus,40 liquid ammonia readily dissolves sodium and potassium iodides. The partial press, of ammonia in soln. of potassium iodide at 25°, as measured by R. Abegg and H. Riesenfeld, is raised from 13 45 mm. of water to 13 28, and 14 88 mm. for 0 5W-, N-, and l 5Ar-soln. respectively. H. M. Dawson and J. McCrae have shown that the distribution of ammonia between water and chloroform is generally lowered by the addition of various salts of the alkali metals and ammonium which they tried—halides, nitrates, chlorates, oxalates, sulphates, carbonates, hydroxides this means that the solvent power of aq. soln. of the alkali salts is in general less than that of pure water—lithium chloride, ammonium bromide, and sodium iodide act in the opposite way. The other halide salts of lithium were not tried. The change produced in the partition coeff. by the halides, at 20°, is as follows ... 

When sulphuric arid only is employed, the sulphate of mercury obtained by evaporation is mixed with two parts of metal, and afterwards with one part and a half of common salt, the whole bring triturated in a mortal till the metal disappears. The mass is then sublimed in the asual way. In this operation the whole of the mercury is, however, never reduced to calomel, and on this account the sublimed mass requires purification from corrosive sublimate by repeated washings with boiling water, in which the latter is freely soluble. As soon as the washings give but faint indications of precipitates with a solution of nitrata of silver or sulphide of hydrogen gae, the calomel may be considered pure. 

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