Barium carbonate

“ The operation for producing ammonia and regenerating the carbonate of barium by acting upon the cyanide with steam offers no difficulty whatever, and if the temperature is not allowed to exceed 500° C., the results are quantitative. The regenerated carbonate of barium acts actually better than the ground witherite used in the first instance, and if care is taken that no impurities are introduced by the pitch which is used to remake the briquettes and to replace the small amount of carbon consumed at each operation, I see no reason why it should not continue to act for a very long time. ”

“ Commercial chloride of barium thus purified is probably the most convenient source of the other compounds of barium when required pure. Thus pure carbonate of baryta may be prepared from it by precipitation with carbonate of ammonia, or with carbonate of soda, which is free from silica, sulphuric acid and phosphoric acid.15
14 It may be that leaden pans are used for the evaporation or cry­stal­li­za­tion of the commercial chloride of barium, which would sufficiently account for the presence of lead in the product. ”

“ At a red heat nitrogen combines with boron, titanium, and silicon, barium, magnesium, &c., forming very stable nitrogenous compounds, [6] whose properties are entirely different from those of nitrogen with hydrogen, oxygen and carbon. However, the combination of nitrogen with carbon, although it does not take place directly between the elements at a red heat, yet proceeds with comparative ease by heating a mixture of charcoal with an alkaline carbonate, especially potassium carbonate or barium carbonate, [228] to redness, carbo-nitrides or cyanides of the metals being formed ”

“ The ignited mass should have a slightly blackish tinge to prove the conversion of the nitrates into carbonates. White portions may be locally retreated with oxalic acid. The ignited mass is treated with a small amount of water, which dissolves the alkaline carbonates and leaves the magnesium carbonate, manganese protosesquioxid, and the excess of barium carbonate behind. The alkalies are separated by filtration into a small platinum dish (filtrate D) , and the residue is well but sparingly washed with water on a small filter. ”

“ The valerianic acid thus formed is now separated by distilling the mixture of water and chloroform. The distillate is digested with barium carbonate, next concentrated by evaporation, and then filtered, and divided into two equal portions. One portion is evaporated to dryness, the residue taken up with water containing a little nitric acid, and the amount of barium present determined by precipitation with sulphuric acid. In the other portion, the chlorine originating from a partial oxidation of the chloroform, is to be estimated. ”

“ It crystallizes in the monoclinic system, and separates from its aqueous solution as Ba (BrO3) 2 · H2O. On heating, it begins to decompose at 260-265° C. Barium chlorate, Ba (ClO3) 2, is obtained by adding barium chloride to sodium chlorate solution; on concentration of the solution sodium chloride separates first, and then on further evaporation barium chlorate crystallizes out and can be purified by recrystallization. It can also be obtained by suspending barium carbonate in boiling water and passing in chlorine. ”

“ After the administration per os, much of the barium must be carried off in the diarrheal stools. A number of deaths in horses have been attributed to the use of this agent. No doubt the presence of sulphates, etc., derived from the food would render the barium insoluble in the gastro-intestinal tract, and this would explain the lack of poisonous action in certain of the cases in which large doses of barium proved harmless.
Husard and Biron administered daily doses of 8 grams of barium chlorid to one horse, and the same amount of barium carbonate to a second horse, for several days. ”

“ Barium forms numerous salts, which are all either colourless or white, except a few, whose acids are coloured, as the chromate, manganate, &c. Some of them are soluble in water; one or two only are soluble in alcohol, and that very sparingly; and (with the exception of the sulphate) they are all extremely poisonous. They may be prepared by saturating solutions of the acids with either baryta-water, or carbonate of barium; and some of them may be prepared by double decomposition. ”

“ By means of barium carbonate [p195] we can, therefore, precipitate the hydroxides of the aluminium group without precipitating the ions of the zinc group. The separation is carried out in a, practically, neutral medium (free carbonic acid in excess is evolved; barium carbonate alone, when treated with water, is slightly alkaline) and thus avoids the error of facilitating the precipitation of the bivalent metals in the shape of salts of the acidic forms of the trivalent metals, i.e. ”

“ Barium is another metal which does not occur in its native state in Nature. It has only been isolated as a yellow powder, which, exposed to air or water, soon changes to one of the oxides. Both barium and its compounds are peculiar in causing a green color, whenever exposed to the flame. Two of its compounds are fairly abundant, the sulphate, barite, and the carbonate, witherite. ”

“ It is found in the crude state abundantly in nature, but can only be obtained absolutely pure by adding an alkaline carbonate to a solution of chloride of barium, or by saturating the hydrate with carbonic anhydride, and in either case washing and drying the precipitate. ”

“ Carbonate of potassium deliquesces in the air, and is almost entirely dissolved by water; in an open vessel it spontaneously liquefies. It changes the colour of turmeric brown. Supersaturated with nitric acid, neither carbonate of sodium nor chloride of barium throws down anything, and nitrate of silver very little. 100 gr. lose 16 gr. of water by a strong red heat; and the same weight loses 26·3 gr. of carbonate anhydride when placed in contact with dilute sulphuric acid. ”

“ This is effected by heating a mixture of the fuel with lime and sodium carbonate in a porcelain dish to redness in a muffle until all the carbonaceous matter has been burnt off. The residue, which contains the sulphur as calcium sulphate, is transferred to a beaker containing water to which a little bromine has been added. Hydrochloric acid is carefully added, the liquid filtered and the residue washed. To the filtrate ammonia is added, and then barium chloride, which precipitates the sulphur as barium sulphate. ”

“ Heat the solution of sulphate of magnesia to the boiling point, add the solution of carbonate of soda, and boil together until carbonic acid ceases to be evolved. Collect the precipitated carbonate of magnesia, and wash until what passes ceases to give a precipitate with chloride of barium. Mix the precipitate with a pint of distilled water, and in a suitable apparatus, charge with pure washed carbonic acid gas. Retain excess of carbonic acid under pressure for 24 hours. Filter to remove undissolved carbonate, and again pass carbonic acid into the solution. ”

“ In this way the crude sulphates of barium containing radium and calcium, of lead, and of iron, and of a trace of actinium are obtained. The solution still contains a little actinium and polonium, which may be separated out as in the case of the first hydrochloric acid solution.
From one ton of residue 10 to 20 kilogrms. of crude sulphates are obtained, the activity of which is from thirty to sixty times as great as that of metallic uranium. They must now be purified. For this purpose they are boiled with sodium carbonate and transformed into the chlorides. ”

“ But the addition of carbonic acid to barium chloride solutions fails to produce the slightest precipitate (exp.) , although carbonic acid also gives rise to the carbonate-ion, CO32−. In the same way silver nitrate readily precipitates silver phosphate from sodium phosphate solutions (exp.) , but not from a solution of phosphoric acid (exp.) . Hydrogen sulphide precipitates zinc sulphide from a zinc sulphate solution (exp.) ”

“ The baryta is mixed with a portion of hydrate of calcium or of magnesium, and the mixture being placed in an appropriate earthen tube heated to dull redness, is oxidised by passing a current of dry atmospheric air over it. As soon as the oxidation is complete, the tube is connected with the gas-holder, and a jet of steam allowed to act upon it; this reconverts the peroxide of barium into hydrate of barium, the excess of oxygen being given off and collected in the gas-holder. ”

“ Carbon dioxide, which is formed by the complete oxidation of carbon, is a gas with a sweetish odour and taste, having a strong affinity for alkalies, and forming a series of compounds termed carbonates. The gas itself occurs in nature, and is sometimes met with in quantity in mining. The carbonates occur largely in nature, forming mountain masses of limestone, &c. Carbonates of many of the metals, such as carbonate of lead (cerussite) , carbonate of iron (chalybite) , carbonates of copper (malachite and chessylite) , and carbonate of magnesia (magnesite) , are common. ”

“ The metallic compounds formed by the combination of persulphomolybdic acid with a base are pulverulent, in many cases of a red colour, and for the most part insoluble in water. With barium, the acid furnishes a yellowish-red powder, insoluble in, but made denser by water, which imparts to it a cinnabar colour. With calcium it is said to yield a scarlet, sparingly soluble in water. With chromium, uranium, lead, platinum, and copper, it gives a dark red; that from the last metal turning brown when collected on a filter. It likewise produces reds with zinc, cadmium, iron, mercury, and tin ”

“ The metallic base of these salts is barium. It is a white, malleable, and fusible metal, readily oxidizing in air, and decomposing water at common temperature. The pure baryta, oxide of barium, is used for the production of peroxide of hydrogen, which is much recommended as a medicinal reagent, and employed in the arts for bleaching animal tissue, and converting brown into blond hair. The oxide, or caustic baryta, rivals, in caustic properties, potash, soda, and ammonia. ”

“ Barium occurs chiefly in the form of barytes or heavy spar, BaSO4, and witherite, BaCO3, and to a less extent in baryto-calcite, baryto-celestine, and various complex silicates. The metal is difficult to isolate, and until recently it may be doubted whether the pure metal had been obtained. Sir H. Davy tried to electrolyse baryta, but was unsuccessful; later attempts were made by him using barium chloride in the presence of mercury. In this way he obtained an amalgam, from which on distilling off the mercury the barium was obtained as a silver white residue. ”

“ The mass becomes semi-liquid, and when it evolves carbonic oxide the heating is stopped. The following double decompositions proceed during this operation: first the carbon takes up the oxygen from the barium sulphate, and gives sulphide, BaS, which enters into double decomposition with the chloride of manganese, MnCl2, forming manganese sulphide, MnS, which is insoluble in water, and soluble barium chloride. ”

“ A. N. Guntz (Comptes rendus, 1901, 133, p. 872) electrolyses a saturated solution of barium chloride using a mercury cathode and obtains a 3% barium amalgam; this amalgam is transferred to an iron boat in a wide porcelain tube and the tube slowly heated electrically, a good yield of pure barium being obtained at about 1000° C. The metal when freshly cut possesses a silver white lustre, is a little harder than lead, and is extremely easily oxidized on exposure; it is soluble in liquid ammonia, and readily attacks both water and alcohol. ”

“ In pharmacy, &c., chiefly to prepare barium salts. In chemistry, to separate certain metallic oxides when occurring together in solutions. In the arts, as a base for certain delicate colours, as an ingredient in plate-glass, in the manufacture of beet sugar, &c. It is not used in medicine. It is extremely poisonous.
Barium, Bisulphide. This substance may be obtained as a fine yellow-coloured product by shaking a solution of barium chloride with a mixture of ammonium sulphide and carbon disulphide. It is insoluble in alcohol, soluble in water, and rapidly dissolved by slightly acidulated water. ”

“ Especially remarkable are the experiments of A. Debierne, which have been conducted in a similar manner with actinium, and by which it was proved that it is easy to make active the compounds of barium so that they scarcely differ from those of radium, except that they do not give a radium spectrum. The active barium is said to stand between barium and radium, its anhydrous chloride is self-luminous like that of radium, and may equally well, by fractional crystallization, be separated in a more active and a less active portion. ”

“ The retort is to be gradually heated to redness, and retained at that temperature as long as nitrous acid and azotic gas pass over; the evolution of these substances indicates that nitrate of baryta still remains to be decomposed, but the instant that pure oxygen gas passes off, the fire is to be removed and the retort cooled. The product of this decomposition is a peroxide of barium; it falls to pieces in water, without producing heat, disengages oxygen when boiled with water, and is reduced to a protoxide by a strong heat. When acted upon by sulphuric acid, no nitric acid was evolved ”