Silver chloride sulphate

It has been prepared synthetically by Ewins in the following manner Meta-oxybenzoic acid is converted with the aid of dimethyl sulphate into m-methoxybenzoic acid, which is then nitrated, and from the nitration products 2-nitro-3-methoxybenzoic acid is separated. This is reduced to 2-amino-3-methoxybenzoic acid which on heating with methyl iodide, yields 2-methylamino-3-methoxybenzoic acid. On warming this with freshly precipitated silver chloride it yields damascenine hydrochloride. 

Various types of reference electrodes have been considered in Section 20.3, and the potentials of these electrodes and their variation with the activity of the electrolyte are listed in Table 21.7, Chapter 21. It is appropriate, however to point out here that the saturated calomel electrode (S.C.E.), the silver-silver chloride electrode and the copper-copper sulphate electrode are the most widely used in corrosion testing and monitoring. 

Mercury/mercurous sulphate (Hg/HgSOj, SOJ ) Silver/silver chloride (Ag/AgCl, Cl )... 

The solubility of the precipitates encountered in quantitative analysis increases with rise of temperature. With some substances the influence of temperature is small, but with others it is quite appreciable. Thus the solubility of silver chloride at 10 and 100 °C is 1.72 and 21.1mgL 1 respectively, whilst that of barium sulphate at these two temperatures is 2.2 and 3.9 mg L 1 respectively. In many instances, the common ion effect reduces the solubility to so.small a value that the temperature effect, which is otherwise appreciable, becomes very small. Wherever possible it is advantageous to filter while the solution is hot the rate of filtration is increased, as is also the solubility of foreign substances, thus rendering their removal from the precipitate more complete. The double phosphates of ammonium with magnesium, manganese or zinc, as well as lead sulphate and silver chloride, are usually filtered at the laboratory temperature to avoid solubility losses. 

Determination of chlorate as silver chloride Discussion. The chlorate is reduced to chloride, and the latter is determined as silver chloride, AgCl. The reduction may be performed with iron(II) sulphate solution, sulphur dioxide, or by zinc powder and acetic (ethanoic) acid. Alkali chlorates may be quantitatively converted into chlorides by three evaporations with concentrated hydrochloric acid, or by evaporation with three times the weight of ammonium chloride. 

Determination of perchlorate as silver chloride Discussion. Perchlorates are not reduced by iron (II) sulphate solution, sulphurous acid, or by repeated evaporation with concentrated hydrochloric acid reduction occurs, however, with titanium(III) sulphate solution. Ignition of perchlorates with ammonium... 

The following facts must be borne in mind. All strong electrolytes are completely dissociated hence only the ions actually taking part or resulting from the reaction need appear in the equation. Substances which are only slightly ionised, such as water, or which are sparingly soluble and thus yield only a small concentration of ions, e.g. silver chloride and barium sulphate, are, in general, written as molecular formulae because they are present mainly in the undissociated state. 

Silver bromide Silver chloride Silver perchlorate Silver cyanide Silver fluoride Silver iodide Silver permar>gate Silver nitrate Silver carbonate Silver oxide Silver sulphate Silver sulphide Silver phosphate... 

The described electrodes, and especially the silver chloride, calomel and mercurous sulphate electrodes are used as reference electrodes combined with a suitable indicator electrode. The calomel electrode is used most frequently, as it has a constant, well-reproducible potential. It is employed in variously shaped vessels and with various KC1 concentrations. Mostly a concentration of KC1 of 0.1 mol dm-3, 1 mol dm-3 or a saturated solution is used (in the latter case, a salt bridge need not be employed) sometimes 3.5 mol dm-3 KC1 is also employed. The potentials of these calomel electrodes at 25°C are as follows (according to B. E. Conway) ... 

Silver chloride is fairly insoluble (see p. 332), with a solubility product Ksp of 1.74 x 1CT10 mol2 dm-6. Its concentration in pure distilled water will, therefore, be 1.3 x 10-5 mol dm-3, but adding magnesium sulphate to the solution increases it solubility appreciably see Figure 7.10. 

Organic carbon can be determined in calcareous soils after the carbonates have been removed by treatment with sulphuric acid-iron(II) sulphate solution and the samples oven-dried at 105°C. However, as in all other wet-combustion methods, chloride ions interfere [7]. Interference from small amounts of chloride ions (up to 4mg of Ch as KC1 or NaCl) was reduced by adding 2.5% of mercury II oxide or silver I sulphate to the acid digestion mixture. 

Complexes are also known in which the co-ordination numbers- are one, two, three, five, seven, and even eight respectively, but these are less frequent. As examples may be mentioned sulphito-coppcr potassium, [Cu(S03)]K, and the unstable nitroso-ferrous sulphate, [Fe(N0)]S04, each of which possess unit co-ordination number. l)i-ammino-silvcr chloride, [Ag(NH3)2]Cl, and triammino-silver chloride. [Ag(NIT3)3]Cl, possess co-ordination numbers two and three respectively. In penta-phenylhydrazino-zine sulphate, [Zn(NHa.NH.C6II5)5JS04, and octammino-strontium chloride, [Sr(NH3)8]Cl2, the co-ordination numbers are five and eight respectively. 

Nitro-pentammino-chromic Sulphate, [Cr(NH3)6N02]S04, is formed by rubbing the chloride with water and the calculated quantity of silver sulphate, filtering off silver chloride and precipitating the salt from the filtrate with alcohol. 

Chloro-pentammino-chromic Sulphate, [Cr(N I3)5Cl]S04.2H20, is prepared by treating the chloride with silver carbonate, removing the precipitated silver chloride and cautiously adding to the liquid dilute sulphuric acid a little silver chloride is thereby precipitated, it is removed by filtration, and the sulphate is precipitated from the filtrate by means of alcohol in carmine-red prisms. It is fairly soluble in water, and loses water if left over sulphuric acid or on heating to 100° C. 

Silver foil is transformed by an aq. soln. of the trichloride into silver chloride and iodide silver oxide with an excess of the trichloride is transformed into the chloride and iodic acid with more silver oxide, silver iodate is formed and with an excess of the oxide and a boiling soln. some silver periodate is formed. Mercuric oxide is slowly transformed into mercuric chloride and oxide chlorine, oxygen, and possibly chlorine monoxide are evolved. Aq. soln. of the trichloride give a precipitate of iodine with a little stannous chloride with more stannous chloride, some stannous iodide is formed. Consequently, although chloroform extracts no iodine from the aq. soln., it will do so after the addition of stannous chloride. Sulphur dioxide and ferrous sulphate are oxidized. 

Potassium sulphate, when warmed with chlorosulphonic acid, yields potassium pyrosulphate,9 the reaction being analogous to that of sulphuric acid with the chloro-aeid silver nitrate is vigorously converted into silver chloride, with concurrent formation of nitrosulphonic acid.10... 

Condensation between phenol and selenium oxychloride in ether or chloroform solution produces two isomeric selenonium chlorides, [(HO.CeH4)3Se]Cl, each containing chlorine precipitable as silver chloride and replaceable by other acid radicals. The three phenolic hydroxyl groups of the complex cation impart acidic properties to the chlorides, causing them to be soluble in aqueous caustic alkali. From such solutions carbonic or acetic acid precipitates the amphoteric oxide [(H0.C6H4)8Se]20, which redissolves in alkalis and reacts with acids to give a bromide, nitrate, sulphate and chloroplatinate. The following scheme shows the compounds obtained ... 

Two of the preceding investigators determined the chlorine in the compound by weighing it as silver chloride first, Bailey and Lamb, who collected the ammonium chloride evolved when pailadosammine chloride was heated in hydrogen and, secondly, Amberg, who precipitated the chloride in his filtrates after removing the palladium (electrolytically in series (i) and with hydrazine sulphate in series (iii) above) ... 

Do not mistake precipitated silver sulphate for silver chloride. In a modification of this method, lead dioxide is substituted for potassium peroxodisulphate. Acidify the solution with acetic acid, add lead dioxide, and boil the mixture until bromine and iodine are no longer evolved. Filter, and test the filtrate, which should be colourless, with silver nitrate solution and dilute nitric acid. 

Acidify 3 ml of the soda extract with concentrated perchloric acid and add 1 ml in excess (note 2 below) add silver nitrate solution, slowly and with stirring, until precipitation is complete. Filter and collect the filtrate in a ground-glass stoppered conical flask or test-tube. Add m sodium chloride solution, 05 ml at a time, to the filtrate until no more precipitate forms. Stopper the flask or test-tube and shake the mixture vigorously after each addition. Filter off the silver chloride (note 3 below), transfer the filtrate to the stoppered vessel, add an equal volume of concentrated hydrochloric acid (if a precipitate of sodium chloride forms, filter), cool, then add 1-2 g solid iron(II) ammonium sulphate and 2 ml carbon tetrachloride. Shake the mixture intermittently for 5 minutes. A purple colour in the carbon tetrachloride indicates periodate present. 

Silver chromate is almost insoluble in water, glacial acetic acid, and in solutions of potassium chromate, but soluble in those of ammonia, caustic alkalies, nitrates, and in dilute acetic acid. A concentrated solution of ammonium nitrate is a good crystallising medium for silver chromate. With chlorine, above 200° C., silver chloride, chromium trioxide, and oxygen are produced. The solution in ammonia contains the compound Ag2Cr04.4NH3, which forms crystals isomorphous with the corresponding ammoniacal sulphate. ... 

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