Zinc Chloride Sulphate

The experimental details for mono-M-propylanillne are as follows. Reflux a mixture of 230 g. of aniline and 123 g. of n-propyl bromide for 8-10 hours. Allow to cool, render the mixture alkafine, and add a solution of 150 g. of zinc chloride in 150 g. of water. Cool the mixture and stir after 12 hours, filter at the pump and drain well. Extract the thick paste several times with boiling light petroleum, b.p. 60-80° (it is best to use a Soxhlet apparatus), wash the combined extracts successively with water and dilute ammonia solution, and then dry over anhydrous potassium carbonate or anhydrous magnesium sulphate. Remove the solvent on a water bath, and distil the residue from a Claisen flask with fractionating side arm (well lagged). Collect the n-propyl-aniline at 218-220° the yield is 80 g. Treat the pasty solid zincichloride with an excess of. sodium hydroxide solution and steam distil 130 g. of pure aniline are recovered. 

Skin Inorganic acids (chromic, nitric) organic acids (acetic, butyric) inorganic alkalis (sodium hydroxide, sodium carbonate) organic bases (amines) organic solvents. Dusts Detergents salts (nickel sulphate, zinc chloride) acids, alkalis, chromates. ... 

Many salts which are corrosive towards unalloyed iron because of their tendency to hydrolyse to release acid, e.g. calcium and zinc chlorides, are not dangerous to high-chromium irons. The more corrosive salts, typified by aluminium sulphate and ferric chloride, are, however, corrosive to high-chromium irons. Hot aluminium sulphate solutions can give corrosion rates greater than 1 27 mm/y although cold solutions corrode the alloys at rates not exceeding 0-127 mm/y. 

Salt solutions When a zinc sheet is immersed in a solution of a salt, such as potassium chloride or potassium sulphate, corrosion usually starts at a number of points on the surface of the metal, probably where there are defects or impurities present. From these it spreads downwards in streams, if the plate is vertical. Corrosion will start at a scratch or abrasion made on the surface but it is observed that it does not necessarily occur at all such places. In the case of potassium chloride (or sodium chloride) the corrosion spreads downwards and outwards to cover a parabolic area. Evans explains this in terms of the dissolution of the protective layer of zinc oxide by zinc chloride to form a basic zinc chloride which remains in solution. 

B. Back-titration. Many metals cannot, for various reasons, be titrated directly thus they may precipitate from the solution in the pH range necessary for the titration, or they may form inert complexes, or a suitable metal indicator is not available. In such cases an excess of standard EDTA solution is added, the resulting solution is buffered to the desired pH, and the excess of the EDTA is back-titrated with a standard metal ion solution a solution of zinc chloride or sulphate or of magnesium chloride or sulphate is often used for this purpose. The end point is detected with the aid of the metal indicator which responds to the zinc or magnesium ions introduced in the back-tit ration. 

Solutions of EDTA of the following concentrations are suitable for most experimental work 0.1M, 0.05M, and 0.01 M. These contain respectively 37.224 g, 18.612g, and 3.7224 g of the dihydrate per litre of solution. As already indicated, the dry analytical grade salt cannot be regarded as a primary standard and the solution must be standardised this can be done by titration of nearly neutralised zinc chloride or zinc sulphate solution prepared from a known weight of zinc pellets, or by titration with a solution made from specially dried lead nitrate. 

Sodium aluminium sulphate Sodium bisulphate Sodium hypochlorite Sodium perchlorate Sodium thiocyanate Stannic ammonium chloride Stannic chloride Stannous chloride Uranyl nitrate Zinc chloride Zinc fluorosilicate... 

Detergents salts (nickel sulphate, zinc chloride) acids, alkalis, chromates. 

DSA-02 oxide-coated Ti anode (DSA = Dimensionally Stable Anode) is placed, thus creating a large cathode volume. The effluent solution flows perpendicularly through the electrodes with a typical flow rate of 0.5 dm3 s-1. The flowthrough metal electrodes have an active area approximately 15 times their geometric area. The cell allows air sparging to increase the mass-transfer. The current efficiency is about 40% when the inlet concentration of the metal ions is 150 to 1500 ppm and the concentration at the out-let is about 50 ppm. The cell is currently used for the treatment of recirculated wash-waters from acid copper, copper cyanide, zinc cyanide, zinc chloride, cadmium sulphate, cadmium cyanide and precious metal plating and washwaters from electroless copper deposition. Since the foam metal electrodes are relatively expensive the electrodes... 

Dimethyl-p-phenylenediamine (7-6 g.) is dissolved in 70 c.c. of iV-hydrochloric acid, and 35 g. of zinc chloride in 50 c.c. of water are added. With good stirring 12 g. of aluminium sulphate in 20 c.c. of water and then 15 g. of sodium thiosulphate in 20 c.c. of water are poured in. To the solution thus obtained one-third of a solution of 16 g. of sodium dichromate in 30 c.c. of water is at once added and the temperature of the solution is raised as rapidly as possible to 40°. The addition of 6 g. of dimethylaniline dissolved in 8 c.c. of concentrated hydrochloric acid follows, and finally the remainder of the oxidising agent is poured in. Of course, all these solutions are prepared before the experiment is begun. 

Ephraim and Bolle 3 find that the stability of the ammines of general formula [M(NII3) ]R2 depends not only on the central atom but also on the anion. These influences oppose one another, and the stability of the whole molecule is therefore the resultant of the two influences consequently, very little parallelism may appear between analogous compounds. For instance, the temperatures of decomposition of the hexanunino-salts of nickel decrease in the order perchlorate, iodide, bromide, chlorate, nitrate, chloride, sulphate whilst in the ease of the liexammino-salts of zinc, the order for decreasing stability is iodide, bromide, chloride, perchlorate, sulphate, nitrate, chlorate. 

The detection and determination ot the perchlorates.—The perchlorates give no precipitates with silver nitrate or barium chloride soln. cone. soln. give a white crystalline precipitate with potassium chloride. Unlike all the other oxy-acids of chlorine, a soln. of indigo is not decolorized by perchloric acid, even after the addition of hydrochloric acid and they do not give the explosive chlorine dioxide when warmed with sulphuric acid unlike the chlorates, the perchlorates are not reduced by the copper-zinc couple, or sulphur dioxide. Perchloric acid can be titrated with —iV-alkali, using phenolphthalein as indicator. The perchlorates can be converted into chlorides by heat and the chlorides determined volumetrically or gravimetrically they can be reduced to chloride by titanous sulphate 28 and titration of the excess of titanous sulphate with standard permanganate they can be fused with zinc chloride and the amount of chlorine liberated can be measured in terms of the iodine set free from a soln. of potassium iodide and they can be... 

Zinc Orthoarsenite, Zn3(As03)2, is obtained7 as a white crystalline precipitate when aqueous arsenious acid is added to a solution of zinc sulphate containing ammonia and ammonium chloride precipitation occurs in the cold, an aggregate of crystalline needles being rapidly formed. A similar precipitate is thrown down by potassium orthoarsenite from a solution of zinc chloride in 50 per cent, alcohol,8 or from a solution of zinc sulphate by potassium tetrarsenite9 or sodium metarsenite.10 Zinc orthoarsenite dissolves readily in acids. It decomposes when heated. 

Basic colouring matters are usually sold as salts—chlorides, sulphates, nitrates, acetates, oxalates or double salts with zinc or ferric chloride. 

The product is then transferred to a large flask and distilled with steam to remove unchanged dimethyl-aniline the leuco-base is filtered when cool and recrystallised from alcohol. Almost a quantitative yield is obtained. The zinc chloride double salt of the dye is prepared as follows Ten. gms. of the base is dissolved in dilute hydrochloric acid containing 2 7 gms. of HC1 the liquid is diluted with 800 c.c. of water and 10 gms. of 40 per cent, acetic acid added it is then cooled with ice, and a thin paste of 7 5 gms. of lead peroxide added gradually with shaking. After standing a few minutes, the lead is precipitated by adding 20 per cent, sodium sulphate, and to tho filtrate from lead sulphate is added 8 gms. of zinc chloride dissolved iu a little water. The dye is then salted out by addition of common salt. Yield, abont 7 gms. 

Two 67Zn (natural abundance = 4.12% / = f) n.m.r. studies have been reported.9,10 The chemical shift of 67Zn (4.81 MHz at 1.807 Tesla) in aqueous zinc chloride, bromide, and iodide solutions was found to be strongly concentration dependent, while no such dependence was noted in solutions of the perchlorate, nitrate, or sulphate. This behaviour resembles that found for analogous cadmium systems, and is attributed to the formation of mono- and poly-halogeno- complexes even at low salt concentrations. In addition, the zinc halide solutions show an anomalous shift to higher frequencies for their solutions in D20, compared with those in H20. The perchlorate, nitrate and sulphate show no solvent isotope effect. 

Wood splinters IV, VIII Zinc metal, dust II Zinc metal, feathered III, VII Zinc chloride II, VII Zinc sulphate II, VII... 

Zinc ferrite, Zn(Fe02)2 or Zn0.Fe203, occurs in nature as frank-linite (see p. 14) and may be artificially prepared in the laboratory in a variety of ways,5 such as by fusing an intimate mixture of the sulphates of sodium, zinc, and ferric iron at cherry-red heat, and extracting the melt with boiling water. Any basic zinc sulphate is removed with dilute acetic acid. Crystalline zinc ferrite also results when zinc chloride is heated in moist air with ferric chloride or haematite. The zinc chloride may be replaced by the corresponding fluoride.6... 

Ferrous sulphide is oxidised by acidulated hydrogen peroxide solution, yielding ferric sulphate or hydrolysed products of this salt.1 With ammoniacal zinc chloride no reaction occurs at the ordinary temperature, but at 160° to 170° C. in a sealed tube ferrous hydroxide and zinc sulphide are produced.2... 

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