Chloride Sentence Examples

In aqueous solution it gives a red colour with ferric chloride.

Silver has been discovered in all the states, either alone or in the form of sulphides, antimonial and arsenical ores, chloride, bromide,.

The hexammine salts are formed by the oxidizing action of air on dilute ammoniacal solutions of cobaltous salts, especially in presence of a large excess of ammonium chloride.

Boron bromide BBr 3 can be formed by direct union of the two elements, but is best obtained by the method used for the preparation of the chloride.

Stannic Chloride, SnC1 4, named by Andreas Libavius in 1605 Spiritus argenti vivi sublimate from its preparation by distilling tin or its amalgam with corrosive sublimate, and afterwards termed Spiritus fumans Libavii, is obtained by passing dry chlorine over granulated tin contained in a retort; the tetrachloride distils over as a heavy liquid, from which the excess of chlorine is easily removed by shaking with a small quantity of tin filings and re-distilling.

The plain chloride solution is similarly used.

Stannous iodide, Sn12, forms yellow red needles, and is obtained from potassium iodide and stannous chloride.

Only stannous salts (not stannic) give a precipitate of calomel in mercuric chloride solution.

Jorgensen in the second dinitrotetramminecobalt chloride, [Co(NO 2) 2 (NH 3) 4 ]Cl, designated as flavo - whereas the older isomer of Gibbs was distinguished as croceo-salt.

Curie obtained only a fraction of a gramme of the chloride and Giesel 2 to 3 gramme of the bromide from a ton of uranium residues.

Bernthsen); by the action of ammonium chloride or hydrochlorides of amines on nitriles; by condensing amines and amides in presence of phosphorus trichloride; by the action of hydrochloric acid on acid-amides (0.

Muthmann and Weiss (Ann., 1904, 33 1, p. 1) obtained it by electrolysing the anhydrous chloride.

By evaporation of a solution of lanthanum oxide in hydrochloric acid to the consistency of a syrup, and allowing the solution to stand, large colourless crystals of a hydrated chloride of the composition 2LaC1 3.15H 2 O are obtained.

Debray prepared it, in a compact state, by reducing the volatilized chloride with melted sodium, in an atmosphere of hydrogen.

Beryllium chloride BeC1 2, like aluminium chloride, may be prepared by heating a mixture of the oxide and sugar charcoal in a current of dry chlorine.

In his researches on the bleaching compounds of chlorine he was the first to advance the view that bleaching-powder is a double compound of calcium chloride and hypochlorite; and he devoted much time to the problem of economically obtaining soda and potash from seawater, though here his efforts were nullified by the discovery of the much richer sources of supply afforded by the Stassfurt deposits.

It may be prepared by the addition of potassium nitrite to an acetic acid solution of cobalt chloride.

In two cases, however, it has been found in the absence of appreciable quantities of uranium and thorium compounds, namely in beryl, and in sylvine (potassium chloride).

Boron nitride BN is formed when boron is burned either in air or in nitrogen, but can be obtained more readily by heating to redness in a platinum crucible a mixture of one part of anhydrous borax with two parts of dry ammonium chloride.

The chloride,CdC1 2, bromide,CdBr 2, and iodide,Cdl2,arealsoknown, cadmium iodide being sometimes used in photography, as it is one of the few iodides which are soluble in alcohol.

The now well-known fact that small doses of poisonous substances may act as stimuli to living protoplasm, and that respiratory activity and growth may be accelerated by chloroform, ether and even powerful mineral poisons, such as mercuric chloride, in minimal doses, offers some explanation of these phenomena of hypertrophy, wound fever, and other responses to the presence of irritating agents.

Ha-lophytes.These are plants living in situations where the substratum contains a high proportion of sodium chloride.

It is insoluble in water,' but readily soluble in carbon bisulphide, sulphur chloride and oil of turpentine.

Sulphur chloride dissolves sulphur with great readiness and is consequently used largely for vulcanizing rubber; it also dissolves chlorine.

The acid is considered to possess the structure 0 2 S(SH) (OH), since sodium thiosulphate reacts with ethyl bromide to give sodium ethyl thiosulphate, which on treatment with barium chloride gives presumably barium ethyl thiosulphate.

Barium chloride is present in some natural waters, and when this is the case the interaction of sulphates results in a deposition of barytes, as has occurred in the pipes and water-boxes of the Newcastle-on-Tyne coal mines.

Another mode of separating the two acids is to convert them into calcium salts, which are then treated with a perfectly neutral solution of cupric chloride, soluble cupric citrate and calcium chloride being formed, while cupric tartrate remains undissolved.

Potash soap with the same reagent undergoes double decomposition - a proportion being changed into a soda soap with the formation of potassium chloride.

There is no separation of underlyes in potash soap, consequently the product contains the whole constituents of the oils used, as the operation of salting out is quite impracticable owing to the double decomposition which results from the action of salt, producing thereby a hard principally soda soap with formation of potassium chloride.

The chloro-bromide and bromide of silver were also included under this term until they were distinguished chemically in 1841 and 1842, and described under the names embolite and bromargyrite (or bromyrite) respectively; the chloride then came to be distinguished as chlorargyrite, though the name cerargyrite is often now applied to this alone.

They are important ores of silver (the pure chloride contains 75.3% of silver), and have been extensively mined at several places in Chile, also in Mexico, and at Broken Hill in New South Wales.

The chloride and chlorobromide have been found in several Cornish mines, but never in very large amounts.

These are washed with ammonium chloride until the filtrate is colourless, ignited, fused with caustic potash and nitre, the melt dissolved in water and nitric acid added to the solution until the colour of potassium ruthenate disappears.

It forms a characteristic explosive silver salt on the addition of ammoniacal silver nitrate to its aqueous solution, and an amorphous precipitate which explodes on warming with ammoniacal cuprous chloride.

Xanthene, C13H100, may be synthesized by condensing phenol with ortho-cresol in the presence of aluminium chloride.

Silver chloride, for example, in whatever manner it may be prepared, invariably consists of chlorine and silver in the proportions by weight of 35'45 parts of the former and 107.93 of the latter.

The distribution of weight in chemical change is readily expressed in the form of equations by the aid of these symbols; the equation 2HC1+Zn =ZnCl2+H2, for example, is to be read as meaning that from 73 parts of hydrochloric acid and 65 parts of zinc, 136 parts of zinc chloride and 2 parts of hydrogen are produced.

This is also the case if two substances are brought together in solution, by the action of which upon each other a third body is formed which is insoluble in the solvent employed, and which also does not tend to react upon any of the substances present; for instance, when a solution of a chloride is added to a solution of a silver salt, insoluble silver chloride is precipitated, and almost the whole of the silver is removed from solution, even if the amount of the chloride employed be not in excess of that theoretically required.

As another instance of this kind, the decomposition of bismuth chloride by water may be cited.

If a very large quantity of water be added, the chloride is entirely decomposed in the manner represented by the equation BiC1 3 -fOH, = BiOCI -F2HC1, Bismuth chloride.

Balard discovered chlorine monoxide in 1834, investigating its properties and reactions; and his observations on hypochlorous acid and hypochlorites led him to conclude that " bleaching-powder " or " chloride of lime " was a compound or mixture in equimolecular proportions of calcium chloride and hypochlorite, with a little calcium hydrate.

However, in 1833, Berzelius reverted to his earlier opinion that oxygenated radicals were incompatible with his electrochemical theory; he regarded benzoyl as an oxide of the radical C 14 H 1Q, which he named " picramyl " (from 7rucp6s, bitter, and &uvyalk, almond), the peroxide being anhydrous benzoic acid; and he dismissed the views of Gay Lussac and Dumas that ethylene was the radical of ether, alcohol and ethyl chloride, setting up in their place the idea that ether was a suboxide of ethyl, (C2H5)20, which was analogous to K 2 0, while alcohol was an oxide of a radical C 2 H 6; thus annihilating any relation between these two compounds.

This compound is readily oxidized to benzoic acid, C 6 H 5 000H, the aromatic residue being unattacked; nitric and sulphuric acids produce nitro-toluenes, C6H4 CH3 N02j and toluene sulphonic acids, C 6 H 4 CH 3 SO 3 H; chlorination may result in the formation of derivatives substituted either in the aromatic nucleus or in the side chain; the former substitution occurs most readily, chlor-toluenes, C 6 H 4 CH 3 Cl, being formed, while the latter, which needs an elevation in temperature or other auxiliary, yields benzyl chloride, C 6 H 5 CH 2 C1, and benzal chloride, C 6 11 5 CHC1 2.

This latter compound may be chlorinated to perchloracetoacrylic chloride (9), from which the corresponding acid (to) is obtained by treatment with water; alkalis hydrolyse the acid to chloroform and dichlormaleic acid (I I).

The solution is filtered off, boiled till free of sulphuretted hydrogen, and ammonium chloride and ammonia added.

In this case, the precipitate is dissolved in as little as possible hydrochloric acid and boiled with ammonium acetate, acetic acid and ferric chloride.

Any lead chloride dissolves, and may be identified by the yellow precipitate formed with potassium chromate.

Silver chloride goes into solution, and may be precipitated by dilute nitric acid.

The residue, which is black in colour, consists of mercuroso-ammonium chloride, in which mercury can be confirmed by its ordinary tests.

Treatment with casutic soda dissolves out aluminium hydroxide, which is reprecipitated by the addition of ammonium chloride.

If barium is present, the solution of the carbonates in hydrochloric acid is evaporated and digested with strong alcohol for some time; barium chloride, which is nearly insoluble in alcohol,is thus separated, the remainder being precipitated by a few drops of hydrofluosilicic acid, and may be confirmed by the ordinary tests.

The substance is heated with metallic sodium or potassium (in excess if sulphur be present) to redness, the residue treated with water, filtered, and ferrous sulphate, ferric chloride and hydrochloric acid added.

The halogens may be sometimes detected by fusing with lime, and testing the solution for a bromide, chloride and iodide in the usual way.

Horbaczewski's method, which consists in boiling the substance with strong potash, saturating the cold solution` with chlorine, adding hydrochloric acid, and boiling till no more chlorine is liberated, and then testing for sulphuric acid with barium chloride.

The other end is connected with the absorption vessels, which consist of a tube (e) containing calcium chloride, and a set of bulbs (f) containing potash solution.

After having previously roasted the tube and copper oxide, and reduced the copper spiral a, the weighed calcium chloride tube and potash bulbs are put in position, the boat containing the substance is inserted (in the case of a difficultly combustible substance it is desirable to mix it with cupric oxide or lead chromate), the copper spiral (d) replaced, and the air and oxygen supply connected up. The apparatus is then tested for leaks.

The increase in weight of the calcium chloride tube gives the weight of water formed, and of the potash bulbs the carbon dioxide.

Ferric chloride colours its aqueous solution violet.

When boiled with calcium chloride and ammonia, salicylic acid gives a precipitate of insoluble basic calcium salicylate, C 6 H 4 ‹ 0 2 i Ca, a reaction which serves to distinguish it from the isomeric metaand para-hydroxybenzoic acids.

This compound gives a blue potassiumand lithium-ultramarine when treated with the corresponding chloride, and an ethyl-ultramarine when treated with ethyl icdide.

The syn-aldoximes or treatment with acetyl chloride readily lose water and yield nitriles; the anti-aldoximes as a rule are acetylated and do not yield nitriles.

In a purer condition it may be obtained by the action of sulphuric acid on a mixture of potassium nitrate and ferrous sulphate, or of hydrochloric acid on a mixture of potassium nitrate and ferric chloride.

The calcium salt, CaN 2 O 2.4H 2 O, formed by the action of calcium chloride on the silver salt in the presence of a small quantity of nitric acid, is a lustrous crystalline powder, almost insoluble in water but readily soluble in dilute acids.

It is readily decomposed by water and alkaline hydroxides, yielding a mixture of nitrite and chloride.

Faraday examined also the electrolysis of certain fused salts such as lead chloride and silver chloride.

Thus the hydroxyl mentioned above decomposes into water and oxygen, and the chlorine produced by the electrolysis of a chloride may attack the metal of the anode.

The salt must therefore be derived from an acid, chloroplatinic acid, H 2 PtC1 6, and have the formula Na 2 PtC1 6, the ions being Na and PtCls", for if it were a double salt it would decompose as a mixture of sodium chloride and platinum chloride and both metals would go to the cathode.

A freedom of interchange is thus indicated between the opposite parts of the molecules of salts in solution, and it follows reasonably that with the solution of a single salt, say sodium chloride, continual interchanges go on between the sodium and chlorine parts of the different molecules.

In such salts as potassium chloride the ions seem to be simple throughout" a wide range of concentration since the transport numbers for the same series of concentrations as those used above run Potassium chloride 0.5 1 5, 0.515, 0.514, 0.513, 0.509, 0.508, 0.507, 0.507, 0.506.

Thus the osmotic pressure, or the depression of the freezing point of a solution of potassium chloride should, at extreme dilution, be twice the normal value, but of a solution of sulphuric acid three times that value, since the potassium salt contains two ions and the acid three.

Results have been obtained for solutions of sugar, where the experimental, number is 1 858, and for potassium chloride, which gives a depression of 3.720.

We may take Arrhenius' first relation as established for the case of potassium chloride.

In simple substances like potassium chloride it seems evident that one kind of dissociation only is possible.

It is necessary to point out that the dissociated ions of such a body as potassium chloride are not in the same condition as potassium and chlorine in the free state.

It is not unlikely, therefore, that even a compound as stable in the solid form as potassium chloride should be thus dissociated when dissolved.

Solid copper chloride is brown or yellow, so that its concentrated solution, which contains both ions and undissociated molecules, is green, but changes to blue as water is added and the ionization becomes complete.

Let us consider the arrangement - silver I silver chloride with potassium chloride solution I potassium nitrate solution I silver nitrate solution I silver.

Silver chloride is a very insoluble substance, and here the amount in solution is still further reduced by the presence of excess of chlorine ions of the potassium salt.

Another method of vulcanizing articles made from cut sheet rubber consists in exposing them to the action of chloride of sulphur.

Either they are placed in a leaden cupboard into which the vapour is introduced, or they are dipped for a few seconds in a mixture of one part of chloride of sulphur and forty parts of carbon disulphide or purified light petroleum.

If a suspension of lead dichloride in hydrochloric acid be treated with chlorine gas, a solution of lead tetrachloride is obtained; by adding ammonium chloride ammonium plumbichloride, (NH 4) 2 PbC1 6, is precipitated, which on treatment with strong sulphuric acid yields lead tetrachloride, PbC1 4, as a translucent, yellow, highly refractive liquid.

This salt gives the corresponding chloride and fluoride with hydrochloric and hydrofluoric acids, and the phosphate, Pb(HP04)2, with phosphoric acid.

Here compounds of divalent lead have not yet been obtained; by acting with zinc ethide on lead chloride, lead tetraethide, Pb(C 2 IH Q) 4, is obtained, with the separation of metallic lead.

Lead chloride, PbC1 2, occurs in nature as the mineral cotunnite, which crystallizes in the rhombic system, and is found in the neighbourhood of volcanic craters.

A basic chloride, Pb(OH)Cl, was introduced in 1849 by Pattinson as a substitute for white lead.

Powdered galena is dissolved in hot hydrochloric acid, the solution allowed to cool and the deposit of impure lead chloride washed with cold water to remove iron and copper.

A chlorofluoride, PbC1F, is obtained by adding sodium fluoride to a solution of lead chloride.

Lead bromide, PbBr 2, a white solid, and lead iodide, PbI 21 a yellow solid, are prepared by precipitating a lead salt with a soluble bromide or iodide; they resemble the chloride in solubility.

Another process depends upon the formation of lead chloride by grinding together litharge with salt and water, and then treating the alkaline fluid with carbon dioxide until it is neutral.

But the most delicate precipitant for lead is sulphuretted hydrogen, which produces a black precipitate of lead sulphide, insoluble in cold dilute nitric acid, less so in cold hydrochloric, and easily decomposed by hot hydrochloric acid with formation of the characteristic chloride.

It appears, therefore, that liquid oxygen is by far the most strongly paramagnetic liquid known, its susceptibility being more than four times greater than that of a saturated solution of ferric chloride.

It is volatile (para-oxybenzaldehyde is not) and gives a violet coloration with ferric chloride.

If much iron should be present in the shale then it is preferable to use potassium chloride in place of potassium sulphate.

As obtained by the reduction of the chloride, it is a steel grey powder of specific gravity 7 06.

A heavy white precipitate, consisting of ammonium chloride and columbium nitride, is thrown down, and the ammonium chloride is removed by washing it out with hot water, when the columbium nitride remains as an amorphous residue (Hall and Smith, loc. cit.).

Phenylnitromethane, C 6 H 5 CH 2 NO 2, isomeric with the nitrotoluenes, is prepared by the action of benzyl chloride on silver nitrite.

Metallic uranium, as shown by Peligot, can be obtained by the reduction of a mixture of dry chloride of potassium and dry uranous chloride, UC1 4, with sodium at a red heat.

Uranous chloride, UC14, was first prepared by Peligot by heating an intimate mixture of the green oxide and charcoal to redness in a current of dry chlorine; it is obtained as sublimate of black-green metallic-looking octahedra.

The chloride is very hygroscopic. By heating in hydrogen it yields the trichloride, UC1 3, and by direct combination with chlorine the pentachloride, UC1 5.

Uranyl chloride, UO 2 C1 2, is a yellow crystalline mass formed when chlorine is passed over uranium dioxide at a red heat.

One part of cream of tartar, two of alum and two of common salt are dissolved in boiling water, and the solution is boiled with granulated metallic tin (or, better, mixed with a little stannous chloride) to produce a tin solution; and into this the articles are put at a boiling heat.

A hydrated tin trioxide, Sn03, was obtained by Spring by adding barium dioxide to a solution of stannous chloride and hydrochloric acid; the solution is dialysed, and the colloidal solution is evaporated to form a white mass of 2Sn03 H20.

Stannous Chloride, SnC1 2, can only be obtained pure by heating pure tin in a current of pure dry hydrochloric acid gas.

The chloride readily combines with water to form a crystallizable hydrate SnCl 2.2H 2 O, known as "tin salt" or "tin crystals."

Hence all tin crystals as kept in the laboratory give with water a turbid solution, which contains stannic in addition to stannous chloride.

In opposition to stannous chloride, even sulphurous acid (solution) behaves as an oxidizing agent.

A strip of metallic zinc when placed in a solution of stannous chloride precipitates the tin in crystals and takes its place in the solution.

Stannous chloride is largely used in the laboratory as a reducing agent, in dyeing as a mordant.

A mixture of stannous and stannic chloride, when added to a sufficient quantity of solution of chloride of gold, gives an intensely purple precipitate of gold purple (purple of Cassius).

The distillate is purified by treatment with lime and calcium chloride, and subsequent distillation.

For this purpose it is best applied as a fine spray, but ethyl chloride is generally found more efficient and produces less subsequent discomfort.

Loeb found experimentally that increase of metabolic products in muscle greatly raised its osmotic pressure, and so it would absorb water from a relatively concentrated sodium chloride solution.

Widal, Lemierre and other French observers have noted a diminution in the excretion of chlorides in nephritis associated with oedema; Widal and Javal found that a chloride-free diet caused diminution in the oedema and a chloride containing diet an increase of oedema.

As sodium chloride is one of the most permeable of crystalloids it seems strange that damage to the renal tissue should impede its excretion.

It was based on an accidental observation of the action of metallic aluminium on amyl chloride, and consists in bringing together a hydrocarbon and an organic chloride in presence of aluminium chloride, when the residues of the two compounds unite to form a more complex body.

Bernthsen (Ann., 1884, 224, p. 1) condensed diphenylamine with fatty acids, in the presence of zinc chloride.

It burns when brought into contact with chlorine, forming silicon chloride and hydrochloric acid.

The hexachloride, Si 2 C1 61 is formed when silicon chloride vapour is passed over strongly heated silicon; by the action of chlorine on the corresponding iodocompound, or by heating the iodo-compound with mercuric chloride (C. Friedel, Comptes rendus, 18 7 1, 73, P. 497).

Triethyl silicol, (C2H5),Si OH, is a true alcohol, obtained by condensing zinc ethyl with silicic ester, the resulting substance of composition, (C2H5)3 SiOC2H51 with acetyl chloride yielding a chloro-compound (C2H5)3SiC1, which with aqueous ammonia yields the alcohol.

Silicobenzoic acid, C 6 H 5 S10.0H, results from the action of dilute aqueous ammonia on phenyl silicon chloride (obtained from mercury diphenyl and silicon tetrachloride).

It is easily broken down by many substances (aluminium chloride, zinc chloride, &c.) into ethyl chloride and carbon dioxide.

In some cases the chlorine is taken up in two instalments, a lower chloride being produced first, to pass ultimately into a higher chloride.

The ultimate chlorination product of copper, CuC1 2, when heated to redness, decomposes into the lower chloride, CuCI, and chlorine.

Hydriodic acid reduces it to hexamethylene" (cyclo-hexane or hexa-hydro-benzene); chlorine and bromine form substitution and addition products, but the action is slow unless some carrier such as iodine, molybdenum chloride or ferric chloride for chlorine, and aluminium bromide for bromine, be present.

Also Marchlewski (in 1899) synthesized cane sugar from potassium fructosate and acetochloroglucose; and after Fischer discovered that acetochlorohexoses readily resulted from the interaction of the hexose penta-acetates and liquid hydrogen chloride, several others have been obtained.

This is generally effected by adding the calculated amount of potassium chloride (of which immense quantities are obtained as a by-product in the Stassfurt salt industry) dissolved in hot water to a saturated boiling solution of sodium nitrate; the common salt, which separates on boiling down the solution, is removed from the hot solution, and on cooling the potassium nitrate crystallizes out and is separated and dried.

The conglomerate consists of rock fragments, sodium chloride and various sulphates, cemented together by gypsum to form a hard compact mass 6 to 10 ft.

The caliche is worked up in loco for crude nitrate by extracting the salts with hot water, allowing the suspended earth to settle, and then transferring the clarified liquor, first to a cistern where it deposits part of its sodium chloride at a high temperature, and then to another where, on cooling, it yields a crop of crystals of purified nitrate.

Borchers and others deposit zinc from the fused chloride.

By heating the nitrate it is obtained as hemimorphous pyramids belonging to the hexagonal system; and by heating the chloride in a current of steam as hexagonal prisms. It is insoluble in water; it dissolves readily in all aqueous acids, with formation of salts.

At a boiling heat, zinc chloride dissolves in any proportion of water, and highly concentrated solutions, of course, boil at high temperatures; hence they afford a convenient medium for the maintenance of high temperatures.

Zinc chloride solution readily dissolves the oxide with the formation of oxychlorides, some of which are used as pigments, cements and for making artificial teeth.

A solution of the oxide in the chloride has the property of dissolving silk, and hence is employed for removing this fibre from wool.

Zinc carbonate, ZnCO 3, occurs in nature as the mineral calamine (q.v.), but has never been prepared artificially, basic carbonates, ZnCO 3 .xZn(OH) 2, where x is variable, being obtained by precipitating a solution of the sulphate or chloride with sodium carbonate.

In the case of acetate the precipitation is quite complete; from a sulphate or chloride solution the greater part of the metal goes into the precipitate; in the presence of a sufficiency of free HC1 the metal remains dissolved; sulphide of ammonium precipitates the metal completely, even in the presence of ammonium salts and free ammonia.

Pharmacology And Therapeutics Of Zinc Compounds Zinc chloride is a powerful caustic, and is prepared with plaster of Paris in the form of sticks for destroying warts, &c. Its use for this purpose at the present day is, however, very rare, the knife or galvanocautery being preferred in most cases.

It may be prepared by fusion of ortho-toluene sulphonic acid with potash; by the action of phosphorus pentoxide on carvacrol; or by the action of zinc chloride on camphor.

Sainte Claire Deville working independently obtained aluminium by the electrolysis of the fused double sodium aluminium chloride.

The solution, if boiled, deposits its titanic oxide as a hydrate called metatitanic acid, TiO(OH) 21 because it differs in its properties from orthotitanic acid, Ti(OH) 4, obtained by decomposing a solution of the chloride in cold water with alkalis.

Titanium trioxide, T103, is obtained as a yellow precipitate by dropping the chloride into alcohol, adding hydrogen peroxide, and finally ammonium carbonate or potash.

Wirthwein, the titanium mineral is fused with carbon in the electric furnace, the carbides treated with chlorine, and the titanium chloride condensed.

It forms addition compounds similar to those formed by stannic chloride, and combines with ammonia to form TiCl 4.8NH 3 and TiC1 4.6NH 3, both of which with liquid ammonia give titanamide, Ti(NH2)4.

Primary amines heated with carbon bisulphide in alcoholic solution are converted into mustard oils, when the dithiocarbamate first produced is heated with a solution of mercuric chloride.

Aromatic Amines.-The aromatic amines in some respects resemble the aliphatic amines, since they form salts with acids, and double salts with platinum chloride, and they also distil without decomposition.

Hofmann), an alcoholic solution of stannous chloride (containing hydrochloric acid) (R.

Tafel, Ber., 1886, 19, p. 1924), by distilling the amido-acids with lime, by heating phenols with zinc chloride ammonia (V.

The secondary amines may be of two types-namely,the purely aromatic amines, and the mixed secondary amines, which contain an aromatic residue and an alkyl group. The purely aromatic amines result upon heating the primary amines with their hydrochlorides, and, in some cases, by heating a phenol with a primary amine and anhydrous zinc chloride.

When heated with monobasic saturated acids and zinc chloride it yields acridines.

By electrolysing an aqueous solution of the chloride with a mercury cathode, a liquid and a solid amalgam, SrHgn, are obtained; the latter on heating gives a mixture of Sr 2 Hg 5 and SrHg 5, and on distillation an amalgam passes over, and not the metal.

Strontium fluoride, SrF 2, is obtained by the action of hydrofluoric acid on the carbonate, or by the addition of potassium fluoride to strontium chloride solution.

It may be obtained crystalline by fusing the anhydrous chloride with a large excess of potassium hydrogen fluoride or by heating the amorphous variety to redness with an excess of an alkaline chloride.

Strontium chloride, SrC1 2.6H 2 O, is obtained by dissolving the carbonate in hydrochloric acid, or by fusing the carbonate with calcium chloride and extracting the melt with water.

The anhydrous chloride is formed by heating strontium or its monoxide in chlorine, or by heating the hydrated chloride in a current of hydrochloric acid gas.

When an alkaline chloride, say sodium chloride, is electrolysed with one electrode immersed in a porous cell, while caustic soda is formed at the cathode, chlorine is deposited at the anode.

The chlorine reacts with the caustic soda, forming sodium hypochlorite, and this in turn, with an excess of chlorine and at higher temperatures, becomes for the most part converted into chlorate, whilst any simultaneous electrolysis of a hydroxide or water and a chloride (so that hydroxyl and chlorine are simultaneously liberated at the anode) also produces oxygen-chlorine compounds direct.

At the same time, the diffusion of these compounds into contact with the cathode leads to a partial reduction to chloride, by the removal of combined oxygen by the instrumentality of the hydrogen there evolved.

In proportion as the original chloride is thus reproduced, the efficiency of the process is of course diminished.

Oettel, using a 20% solution of potassium chloride, obtained the best yield of hypochlorite with a high current-density, but as soon as II% of bleaching chlorine (as hypochlorite) was present, the formation of chlorate commenced.

Hermite, which consisted in the production of bleach-liquors by the electrolysis (according to the 1st edition of the 1884 patent) of magnesium or calcium chloride between platinum anodes carried in wooden frames, and zinc cathodes.

A 10-12% solution of sodium chloride is caused to flow upwards through the apparatus and to overflow into troughs, by which it is conveyed (if necessary through a cooling apparatus) back to the circulating pump. Such a plant has been reported as giving 0.229 gallon of a liquor containing I% of available chlorine per kilowatt hour, or 0.171 gallon per e.h.p. hour.

Similarly, the formation of organic halogen products may be effected by electrolytic chlorine, as, for example, in the production of chloral by the gradual introduction of alcohol into an anode cell in which the electrolyte is a strong solution of potassium chloride.

Calcium chloride must not be used, since it forms a crystalline compound with alcohol.

An alternative method consists in converting it into ethyl benzoate by shaking with benzoyl chloride and caustic soda.

The metal is soluble in solutions of chlorine, bromine, thiosulphates and cyanides; and also in solutions which generate chlorine, such as mixtures of hydrochloric acid with nitric acid, chromic acid, antimonious acid, peroxides and nitrates, and of nitric acid with a chloride.

The atomic weight of gold was first determined with accuracy by Berzelius, who deduced the value 195.7 (H= i) from the amount of mercury necessary to precipitate it from the chloride, and 195.2 from the ratio between gold and potassium chloride in potassium aurichloride, KAuC1 4.

Kriiss worked with the same salt, and obtained the value 195.65; while Mallet, by analyses of gold chloride and bromide, and potassium auribromide, obtained the value 195.77.

But there is much uncertainty as to the mechanism of the process; some authors hold that the soluble chloride is first formed, while others postulate the intervention of a soluble aurate.

Aurous oxide, Au 2 0, is obtained by cautiously adding potash to a solution of aurous bromide, or by boiling mixed solutions of auric chloride and mercurous nitrate.

When a concentrated solution of auric chloride is treated with caustic potash, a brown precipitate of auric hydrate, Au(OH) 3, is obtained, which, on heating, loses water to form auryl hydrate, AuO(OH), and auric oxide, Au 2 0 3.

Auric chloride, or gold trichloride, AuC1 3, is a dark rubyred or reddish-brown, crystalline, deliquescent powder obtained by dissolving the metal in aqua regia.

The gold chloride of commerce, which is used in photography, is really a hydrochloride, chlorauric or aurichloric acid, HAuC1 4.3H 2 O, and is obtained in long yellow needles by crystallizing the acid solution.

Auric chloride combines with the hydrochlorides of many organic bases - amines, alkaloids, &c. - to form characteristic compounds.

Water decomposes it into gold and auric chloride.

Aurous iodide, Aul, is a light-yellow, sparingly soluble powder obtained, together with free iodine, by adding potassium iodide to auric chloride; auric iodide, Au13, is formed as a dark-green powder at the same time, but it readily decomposes to aurous iodide and iodine.

Potassium auricyanide, 2KAu(CN) 4.3H 2 O, is obtained as large, colourless, efflorescent tablets by crystallizing concentrated solutions of auric chloride and potassium cyanide.

Sodium aurothiosulphate, 3Na 2 S 2 O 3 Au2S203.4H20, forms colourless needles; it is obtained in the direct action of sodium thiosulphateongoldinthe presence of an oxidizing agent, or by the addition of a dilute solution of auric chloride to a sodium thiosulphate solution.

The auric chloride is, however, decomposed at the elevated temperature into finely divided metallic gold, which is then readily attacked by the chlorine gas.

Chlorine, generally prepared by the interaction of pyrolusite, salt and sulphuric acid, is led from a suitable generator beneath the false bottom, and rises through the moistened ore, which rests on a bed of broken quartz; the gold is thus converted into a soluble chloride, which is afterwards removed by washing with water.

Chlorine is generated within the barrel from sulphuric acid and chloride of lime.

Pliny shows that for this purpose the gold was placed on the fire in an earthen vessel with treble its weight of salt, and that it was afterwards again exposed to the fire with two parts of salt and one of argillaceous rock, which, in the presence of moisture, effected the decomposition of the salt; by this means the silver became converted into chloride.

In the " dry " methods the silver is converted into sulphide or chloride, the gold remaining unaltered; in the " wet " methods the silver is dissolved by nitric acid or boiling sulphuric acid; and in the electrolytic processes advantage is taken of the fact that under certain current densities and other circumstances silver passes from an anode composed of a gold-silver alloy to the cathode more readily than gold.

The first process consists essentially in heating the alloy with salt and brickdust; the latter absorbs the chloride formed, while the gold is recovered by washing.

Or the alloy is dissolved in aqua regia, the solution filtered from the insoluble silver chloride, and the gold precipitated by ferrous chloride.

In this process all the anode metals pass into solution except iridium and other refractory metals of that group, which remain as metals, and silver, which is converted into insoluble chloride; lead and bismuth form chloride and oxychloride respectively, and these dissolve until the bath is saturated with them, and then precipitate with the silver in the tank.

Oxidizing agents (ferric chloride, &c.) give a blue precipitate with solutions of its salts.

A hydrated disulphide, B12S2.2H20, is obtained by passing sulphuretted hydrogen into a solution of bismuth nitrate and stannous chloride.

Traces of bismuth may be detected by treating the solution with excess of tartaric acid, potash and stannous chloride, a precipitate or dark coloration of bismuth oxide being formed even when only one part of bismuth is present in 20,000 of water.

The tetrachloride is a white crystalline solid which is formed by the action of chlorine on the dichloride or by sulphur chloride on the element.

Tantalic acid, HTa03,, is a gelatinous mass obtained by mixing the chloride with water.

Magnesium sulphate amounts to 4.7% of the total salts of sea-water according to Dittmar, but to 23.6% of the salts of the Caspian according to Lebedinzeff; in the ocean magnesium chloride amounts to 10.9% of the total salts, in the Caspian only to 4.5%; on the other hand calcium sulphate in the ocean amounts to 3.6%, in the Caspian to 6.9 This disparity makes it extremely difficult to view ocean water as merely a watery extract of the salts existing in the rocks of the land.

Pettersson in 1894, two portions of sea-water are collected in glass tubes which have been exhausted of air, coated internally with mercuric chloride to prevent the putrefaction of any organisms, and sealed up beforehand.

Hackspill (Comptes Rendus, 5905, 141, p. 101) finds that metallic caesium can be obtained more readily by heating the chloride with metallic calcium.

The atomic weight of caesium has been determined by the analysis of its chloride and bromide.

Acetylene is readily soluble in water, which at normal temperature and pressure takes up a little more than its own volume of the gas, and yields a solution giving a purple-red precipitate with ammoniacal cuprous chloride and a white precipitate with silver nitrate, these precipitates consisting of acetylides of the metals.

Frank of Charlottenburg, who finds that a concentrated solution of cuprous chloride in an acid, the liquid being made into a paste with kieselgiihr, is the most effective.

Dr P. Wolff has found that when this is used on the large scale there is a risk of the ammonia present in the acetylene forming traces of chloride of nitrogen in the purifying-boxes, and as this is a compound which detonates with considerable local force, it occasionally gives rise to explosions in the purifying apparatus.

Dr Wolff employs purifiers in which the gas is washed with water containing calcium chloride, and then passed through bleaching-powder solution or other oxidizing material.

This anhydrous chloride is reduced to a lower chloride, of composition SmC1 2, when heated to a high temperature in a current of hydrogen or ammonia (Matignon and Cazes, Coupes rendus, 2906, 142, p. 183).

The chloride, SmCl 2, is a brown crystalline powder which is decomposed by water with liberation of hydrogen and the formation of the oxide, Sm 2 O 3, and an oxychloride, SmOC1.

Dorp (Ber.,1874,7,P.578) obtained orthobenzoyl benzoic acid by heating phthalic anhydride with benzene in the presence of aluminium chloride.

Discovered by Boyle in 1661, it was first carefully studied by Dumas and Peligot in 1831; its synthesis from its elements (through methane and methyl chloride) was effected by Berthelot in 1858.

The distillate is treated with anhydrous calcium chloride, the crystalline compound formed with the alcohol being separated and decomposed by redistilling with water.

Its compound with calcium chloride has the formula CaC1 2.4CH 3.

Chemical methods of sterilization have also been suggested, depending on the use of iodine, chlorine, bromine, ozone, potassium permanganate, copper sulphate or chloride and ()their substances.

Phenosafranine is not very stable in the free state; its chloride forms green plates.

Potassium osmichloride, K 2 OsC1 6, is formed when a mixture of osmium and potassium chloride is heated in a current of chlorine, or on adding potassium chloride and alcohol to a solution of the tetroxide in hydrochloric acid.

Zirconium chloride, ZrC1 4, is prepared as a white sublimate by igniting a mixture of zirconia and charcoal in a current of chlorine.

Zirconium bromide, ZrBr 4, is formed similarly to the chloride.

The principal chalybeate springs are the Tewitt well, called by Dr Bright, who wrote the first account of it, the "English Spa," discovered by Captain William Slingsby of Bilton Hall near the close of the r6th century; the Royal Chalybeate Spa, more commonly known as John's Well, discovered in 1631 by Dr Stanhope of York; Muspratt's chalybeate or chloride of iron spring discovered in 1819, but first properly analysed by Dr Sheridan Muspratt in 1865; and the Starbeck springs midway between High Harrogate and Knaresborough.

Electrolysis of lime or calcium chloride in contact with mercury gave similar results.

These chemists electrolyse either pure calcium chloride, or a mixture of this salt with fluorspar, in a graphite vessel which servos as the anode.

Whereas calcium chloride, bromide, and iodide are deliquescent solids, the fluoride is practically insoluble in water; this is a parallelism to the soluble silver fluoride, and the insoluble chloride, bromide and iodide.

Calcium fluoride, CaF2, constitutes the mineral fluor-spar, and is prepared artificially as an insoluble white powder by precipitating a solution of calcium chloride with a soluble fluoride.

Calcium iodide and bromide are white deliquescent solids and closely resemble the chloride.

The mineral brushite, CaHPO 4.2H 2 0, which is isomorphous with the acid arsenate pharmacolite, CaHAs04.2H20, is an acid phosphate, and assumes monoclinic forms. The normal salt may be obtained artificially, as a white gelatinous precipitate which shrinks greatly on drying, by mixing solutions of sodium hydrogen phosphate, ammonia, and calcium chloride.

It is obtained as rhombic plates by mixing dilute solutions of calcium chloride and sodium phosphate, and passing carbon dioxide into the liquid.

Calcium metasilicate, CaSiO 3, occurs in nature as monoclinic crystals known as tabular spar or wollastonite; it may be prepared artificially from solutions of calcium chloride and sodium silicate.

Ammonia is found in small quantities as the carbonate in the atmosphere, being produced from the putrefaction of nitrogenous animal and vegetable matter; ammonium salts are also found in small quantities in rain-water, whilst ammonium chloride (sal-ammoniac) and ammonium sulphate are found in volcanic districts; and crystals of ammonium bicarbonate have been found in Patagonian guano.

It is obtained by the dry distillation of nitrogenous vegetable and animal products; by the reduction of nitrous acid and nitrites with nascent hydrogen; and also by the decomposition of ammonium salts by alkaline hydroxides or by slaked lime, the salt most generally used being the chloride (sal-ammoniac, q.v.) thus 2NH 4 C1+Ca(OH) 2 =CaC1 2 +2H 2 O+2NH 3.

Ammonia gas has the power of combining with many substances, particularly with metallic halides; thus with calcium chloride it forms the compound CaCl 2.8NH 3, and consequently calcium chloride cannot be used for drying the gas.

Chlorine takes fire when passed into ammonia, nitrogen and hydrochloric acid being formed, and unless the ammonia be present in excess, the highly explosive nitrogen chloride NC1 3 is also produced.

By the addition of sodium amalgam to a concentrated solution of ammonium chloride, the so-called ammonium amalgam is obtained as a spongy mass which floats on the surface of the liquid; it decomposes readily at ordinary temperatures into ammonia and hydrogen; it does not reduce silver and gold salts, a behaviour which distinguishes it from the amalgams of the alkali metals, and for this reason it is regarded by some chemists as being merely mercury inflated by gaseous ammonia and hydrogen.

Ammonium nitrite, NH 4 NO 2, is formed by oxidizing ammonia with ozone or hydrogen peroxide; by precipitating barium or lead nitrites with ammonium sulphate, or silver nitrite with ammonium chloride.

The amount of ammonia in ammonium salts can be estimated quantitatively by distillation of the salts with sodium or potassium hydroxide, the ammonia evolved being absorbed in a known volume of standard sulphuric acid and the excess of acid then determined volumetrically; or the ammonia may be absorbed in hydrochloric acid and the ammonium chloride so formed precipitated as ammonium chlorplatinate, (NH4)2PtC16.

The solution of ammonium chloride so obtained is evaporated and the crude ammonium chloride purified by sublimation.

Sal ammoniac (ammonium chloride, British and United States pharmacopoeiae) as used in medicine is a white crystalline odourless powder having a saline taste.

Ammonium chloride has a different action and therapeutic use from the rest of the ammonium salts.

The inhalation of the fumes of nascent ammonium chloride by filling the room with the gas has been recommended in foetid bronchitis.

Though ammonium chloride has certain irritant properties which may disorder the stomach, yet if its mucous membrane be depressed and atonic the drug may improve its condition, and it has been used with success in gastric and intestinal catarrhs of a subacute type and is given in doses of io grains half an hour before meals in painful dyspepsia due to hyperacidity.

With Dr Hugo Miller as his collaborator he published several papers of a chemical character between the years 1856 and 1862, and investigated, 1868-1883, the discharge of electricity through gases by means of a battery of 14,600 chloride of silver cells.

Sodium chloride, or common salt, is exceedingly common, being the chief salt present in sea-water, besides occurring in extensive stratified deposits.

In Wyoming, California and Nevada enormous deposits of carbonates, mixed in some cases with sulphate and with chloride, occur.

These form the principal natural sources of sodium compounds - the chloride as rock salt and in sea-water being of, such predominating importance as quite to outweigh all the others.

Sodium chloride is an important constituent of the waters of Homburg, Wiesbaden, Nauheim and Kissingen.

The olefines may be synthetically prepared by eliminating water from the alcohols of the general formula CnH2n+1 OH, using sulphuric acid or zinc chloride generally as the dehydrating agent, although phosphorus pentoxide, syrupy phosphoric acid and anhydrous oxalic acid may frequently be substituted.

The higher members of the series readily polymerize in the presence of dilute sulphuric acid, zinc chloride, &c. For the first member of the series see Ethylene.

It is rapidly absorbed by an ammoniacal or acid (hydrochloric acid) solution of cuprous chloride.

Quinhydrone, C 6 H40 2 -C 6 H 4 (OH) 2, is formed by the direct union of quinone and hydroquinone or by careful oxidation of hydroquinone with ferric chloride solution.

All commercial caustic potash is contaminated with excess of water (over and above that in the KHO) and with potassium carbonate and chloride; sulphate, as a rule, is absent.

Potassium chloride, KC1, also known as muriate of potash, closely resembles ordinary salt.

For the purpose of the manufacturer of this salt these are assorted into a raw material containing approximately, in Ioo parts, 55-65 of carnallite (representing 16 parts of potassium chloride), 20-25 of common salt, 15-20 of kieserite; 2-4 of tachhydrite (CaC12 2MgC12 12H20), and minor components.

The decanted ley deposits on standing a 70% potassium chloride, which is purified by washing with cold water.

The carnallite produced is dissolved in hot water and the solution allowed to cool, when it deposits a coarse granular potassium chloride containing up to 99% of the pure substance.

It is worked up either for Epsom salt and common salt, or for sodium sulphate and magnesium chloride.

Chemically pure chloride of potassium is most conveniently prepared from the pure perchlorate by heating it in a platinum basin at the lowest temperature and then fusing the residue in a wellcovered platinum crucible.

This product, known as "crude potashes," contains, in addition to carbonate, varying amounts of sulphate and chloride and also insoluble matter.

The purified carbonate (which still contains most of the chloride of the raw material and other impurities) is known as "pearl ashes."

Most of the carbonate which now occurs in commerce is made from the chloride of the Stassfurt beds by an adaptation of the "Leblanc process" for the conversion of common salt into soda ash (see Alkali Manufacture).

It was obtained as a by-product in many chemical reactions, and subsequently used to be extracted from kainite, one of the Stassfurt minerals, but the process is now given up because the salt can be produced cheaply enough from the chloride by decomposing it with sulphuric acid and calcining the residue.

Wood has studied the iridescent colours seen when a precipitate of potassium silicofluoride is produced by adding silicofluoric acid to a solution of potassium chloride, and found that they are due to the same cause, the refractive index of the minute crystals precipitated being about the same as that of the solution, which latter can be varied by dilution.

They are more easily reduced than the corresponding chlorates; an aqueous solution of hydriodic acid giving free iodine and a metallic oxide, whilst aqueous hydrochloric acid gives iodine trichloride, chlorine, water and a chloride.

The soluble salts are removed by lixiviation, and the residue is boiled with lime to form the soluble calcium ferrocyanide, which is finally converted into the potassium salt by potassium chloride or carbonate.

The metallic cyanides may be detected by adding ferrous sulphate, ferric chloride, and hydrochloric acid to their solution, when a precipitate of Prussian blue is produced; if the original solution contains free acid it must be neutralized by caustic potash before the reagents are added.

The amount of hydrocyanic acid in a solution may be determined by adding excess of caustic potash and a small quantity of an alkaline chloride, and running into the dilute solution standard silver nitrate until a faint permanent turbidity (of silver chloride) is produced, that is, until the reaction, 2KNC+AgNO 3 = KAg(NC) 2 - -KNO 3, is completed.

It is distinguished from the other members of the series by certain characteristic properties; for example, it shows an aldehydic character in reducing silver salts to metallic silver, and it does not form an acid chloride or an acid anhydride.

It is basic in character, and gives a red coloration on the addition of ferric chloride.

Chromic acid and its salts, the chromates and bichromates, can be detected by the violet coloration which they give on addition of hydrogen peroxide to their dilute acid solution, or by the fact that on distillation with concentrated sulphuric acid and an alkaline chloride, the red vapours of chromium oxychloride are produced.

Normal chromates on the addition of silver nitrate give a red precipitate of silver chromate, easily soluble in ammonia, and with barium chloride a yellow precipitate of barium chromate, insoluble in acetic acid.

Chromous oxide, CrO, is unknown in the free state, but in the hydrated condition as Cr04H 2 0 or Cr(OH) 2 it may be prepared by precipitating chromous chloride by a solution of potassium hydroxide in air-free water.

Chromous chloride, CrC1 2, is prepared by reducing chromic chloride in hydrogen; it forms white silky needles, which dissolve in water giving a deep blue solution, which rapidly absorbs oxygen, forming basic chromic salts, and acts as a very strong reducing agent.

On pouring a solution of chromous chloride into a saturated solution of sodium acetate, a red crystalline precipitate of chromous acetate is produced; this is much more permanent in air than the other chromous salts and consequently can be used for their preparation.

Chromic salts are of a blue or violet colour, and apparently the chloride and bromide exist in a green and violet form.

Chromic chloride, CrC1 31 is obtained in the anhydrous form by igniting a mixture of the sesquioxide and carbon in a current of dry chlorine; it forms violet laminae almost insoluble in water, but dissolves rapidly in presence of a trace of chromous chloride; this action has been regarded as a catalytic action, it being assumed that the insoluble chromic chloride is first reduced by the chromous chloride to the chromous condition and the original chromous chloride converted into soluble chromic chloride, the newly formed chromous chloride then reacting with the insoluble chromic chloride.

Solutions of chromic chloride in presence of excess of acid are green in colour.

Chromic bromide, CrBr 3, is prepared in the anhydrous form by the same method as the chloride, and resembles it in its properties.

The fluoride, CrF3, results on passing hydrofluoric acid over the heated chloride, and sublimes in needles.

Potassium chlorochromate, CrO 2 Cl OK, is produced when potassium bichromate is heated with concentrated hydrochloric acid and a little water, or from chromium oxychloride and saturated potassium chloride solution, when - it separates as a red crystalline salt.

By passing ammonia over heated chromic chloride, the nitride, CrN, is formed as a brownish powder.

Their configuration was determined by their relationship to their oxalo-derivatives; the cis-dichloro chloride, [CrC 2 H 4 (NH 2) 2 C1 2 ]Cl-H 2 0, compound with potassium oxalate gave a carmine red crystalline complex salt, [Cr{C2H4(NH2)2}C204][CrC2H4(NH2)2-(C204)2]12H20, while from the trans-chloride a red complex salt is obtained containing the unaltered trans-dichloro group [CrC2H4(NH2)2 C12]

Witt (Ber., 1877, 10, p. 656), is obtained by coupling phenyl diazonium chloride with meta-phenylene diamine.

The constitution of methyl orange follows from the fact that on reduction by stannous chloride in hydrochloric acid solution it yields sulphanilic acid and para-aminodimethyl aniline.

The use of tin salts, especially stannic chloride, SnC1 4, enables dyers to weight all colours the same as black.

Heated with anhydrous sodium acetate and acetic anhydride it gives cinnamic acid; with ethyl bromide and sodium it forms triphenyl-carbinol (C 6 H 5) 3 C OH; with dimethylaniline and anhydrous zinc chloride it forms leuco-malachite green C6H5CH[C6H4N(CH3)2]2; and with dimethylaniline and concentrated hydrochloric acid it gives dimethylaminobenzhydrol, C 6 H 5 CH(OH)C 6 H 4 N(CH 3) 2.

Magnesium is found widely distributed in nature, chiefly in the forms of silicate, carbonate and chloride, and occurring in the minerals olivine, hornblende, talc, asbestos, meerschaum, augite, dolomite, magnesite, carnallite, kieserite and kainite.

Bunsen, in 1852, electrolysed fused magnesium chloride in a porcelain crucible.

In later processes, carnallite (a natural double chloride of magnesium and potassium) has commonly, after careful dehydration, been substituted for the single chloride.

Graetzel's process, which was at one time employed, consisted in electrolysing the chloride in a metal crucible heated externally, the crucible itself forming the cathode, and the magnesium being deposited upon its inner surface.

The solidified chloride is then broken up, the shots and fused masses of magnesium are picked out, run together in a plumbago crucible without flux, and poured into a suitable mould.

Smaller pieces are thrown into a bath of melted carnallite and pressed together with an iron rod, the bath being then heated until the globules of metal float to the top, when they may be removed in perforated iron ladles, through the holes in which the fused chloride can drain away, but through which the melted magnesium cannot pass by reason of its high surface tension.

It is also formed as a by-product in the manufacture of potassium chloride from carnallite.

To obtain the anhydrous salt, the double magnesium ammonium chloride, MgCl2 NH 4 C1.6H 2 O, is prepared by adding ammonium chloride to a solution of magnesium chloride.

The solution is evaporated, and the residue strongly heated, when water and ammonium chloride are expelled, and anhydrous magnesium chloride remains.

Magnesium chloride readily forms double salts with the alkaline chlorides.

A strong solution of the chloride made into a thick paste with calcined magnesia sets in a few hours to a hard, stone-like mass, which contains an oxychloride of varying composition.

C. Marignac has prepared it by the action of calcium carbonate on magnesium chloride.

It is prepared by adding sodium phosphate to magnesium sulphate in the presence of ammonia and ammonium chloride.

The magnesium salts may be detected by the white precipitate formed by adding sodium phosphate (in the presence of ammonia and ammonium chloride) to their solutions.

Recent work has shown it is too feeble to be relied upon alone, but where really efficient antiseptics, such as mercuric chloride and iodide, and carbolic acid, have been already employed, boracic acid (which, unlike these, is non-poisonous and non-irritant) may legitimately be used to maintain the aseptic or non-bacterial condition which they have obtained.

The simplest case is that of water and a salt, such as sodium chloride, which crystallizes without water.

At A we 66 have the freezing point of pure water, which is lowered by the gradual addition of 46 ferric chloride in the manner shown by the curve AB.

In order to explain the electrical properties of a solution, for instance of potassium chloride, we are driven to believe that each molecule of the salt is dissociated into two parts, potassium and chlorine, each associated with an electric charge equal in amount but opposite in sign.

Thus cupric chloride dissolves in much water with an evolution of heat, but when the solution is nearly saturated, it is cooled by taking up more of the solid.

Other substances give equally good agreements; thus sodium chloride has a calculated constant of 1.12 and an observed one of 1.11.

At once observing the reduction of the chloride, he realized the importance of his discovery and immediately began to study the commercial production of the metal.

Deville first selected the chloride as his raw material, but observing it to be volatile and extremely deliquescent, he soon substituted in its place a double chloride of aluminium and sodium.

Molten cryolite dissolves roughly 30% of its weight of pure alumina, so that when ready for treatment the solution contains about the same proportion of what may be termed "available" aluminium as does the fused double chloride of aluminium and sodium.

Alumina dissolves readily enough in aqueous hydrochloric acid to yield a solution of the chloride, but neither this solution, nor that containing sodium chloride, can be evaporated to dryness without decomposition.

To obtain the anhydrous single or double chloride, alumina must be ignited with carbon in a current of chlorine, and to exclude iron from the finished metal, either the alumina must be pure or the chloride be submitted to purification.

This purified oxide, mixed with sodium chloride and coal tar, was carbonized at a red heat, and ignited in a current of dry chlorine as long as vapours of the double chloride were given off, these being condensed in suitable chambers.

For the production of the final aluminium, ioo parts of the chloride and 45 parts of cryolite to serve as a flux were powdered together and mixed with 35 parts of sodium cut into small pieces.

It consisted simply in reducing cryolite with metallic sodium exactly as in Deville's chloride method, and it was claimed to possess various mythical advantages over its rival.

Minet took out patents for electrolysing a mixture of sodium chloride with aluminium fluoride, or with natural or artificial cryolite.

Aluminium hydrate, Al(OH) 3, is obtained as a gelatinous white precipitate, soluble in potassium or sodium hydrate, but insoluble in ammonium chloride, by adding ammonia to a cold solution of an aluminium salt; from boiling solutions the precipitate is opaque.

Aluminium chloride, AlC1 3, was first prepared by Oersted, who heated a mixture of carbon and alumina in a current of chlorine, a method subsequently improved by Wohler, Bunsen, Deville and others.

A purer product is obtained by heating aluminium turnings in a current of dry chlorine, when the chloride distils over.

As a synthetical agent in organic chemistry, aluminium chloride has rendered possible more reactions than any other substance; here we can only mention the classic syntheses of benzene homologues.

Aluminium bromide, AlBr 3, is prepared in the same manner as the chloride.

Chromic acid converts it into phosgene (carbonyl chloride, COC1 2).

By the same method as had succeeded with aluminium (reduction of the chloride by potassium) Wohler in 1828 obtained metallic beryllium and yttrium.

With ferric chloride it gives a dark-blue precipitate of a-dinaphthol, HO C10H6 C10H6.

With ferric chloride it gives a blue coloration.

The sulphate and chloride are similar, but they are not quite so unstable as the nitrate.

Again, the diazonium chlorides combine with platinic chloride to form difficultly soluble double platinum salts, such as (C 6 H 5 N 2 C1) 2 PtC1 4; similar gold salts, C 6 H,N 2 C1 AuC1 3, are known.

Determinations of the electrical conductivity of the diazonium chloride and nitrate also show that the diazonium radical is strictly comparable with other quaternary ammonium ions.

Soc., 1900, 77, p. 69), and sugars are readily oxidized in the presence of ferric chloride (0.

It may be recognized by the violet coloration it gives when added to a very dilute solution of potassium bichromate in the presence of hydrochloric acid; by the orange-red colour it gives with a solution of titanium dioxide in concentrated sulphuric acid; and by the precipitate of Prussian blue formed when it is added to a solution containing ferric chloride and potassium ferricyanide.

The most simple case is presented by the two platinum compounds PtC12(NH3)2, the platosemidiammine chloride of Peyrone, and the platosammine chloride of Jules Reiset, the first formed according to the equation PtC1 4 K 2 + 2NH 3 = PtCl 2 (NH 3) 2 + 2KC1, the second according to Pt(NH 3) 4 C1 2 =PtC1 2 (NH 3) 2 +2NH 3, these compounds differing in solubility, the one dissolving in 33, the other in 160 parts of boiling water.