Ammonium sentence example

ammonium
  • They may be prepared by the dry distillation of the ammonium salts.
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  • They are precipitated from their alkaline solutions as cobalt sulphide by sulphuretted hydrogen, but this precipitation is prevented by the presence of citric and tartaric acids; similarly the presence of ammonium salts hinders their precipitation by caustic alkalis.
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  • Cobalt ammonium phosphate, CoNH4PO 4.12H 2 0, is formed when a soluble cobalt salt is digested for some time with excess of a warm solution of ammonium phosphate.
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  • By dry distillation it gives ammonium cyanide.
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  • It may be obtained in the spongy form by igniting iridium ammonium chloride, and this variety of the metal readily oxidizes when heated in air.
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  • Similar sodium and ammonium compounds are known.
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  • Stas carried out such experiments on the composition of silver chloride and of ammonium chloride, but he never found a variation of one part in 10,000 in the composition of the substances.
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  • Alkaline carbonates give precipitates of basic carbonates, the formation of which is also retarded by the presence of ammonium salts.
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  • 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.
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  • It may also be prepared by heating ammonium oxalate; by passing induction sparks between carbon points in an atmosphere of nitrogen.
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  • 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.
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  • Tetramorphism is exhibited by ammonium nitrate.
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  • Ammonium iodide assumes cubic forms with perfect cubic cleavage; tetramethyl ammonium iodide is tetragonal with perfect cleavages parallel to {100} and {o01} - a difference due to the lengthening of the a axes; tetraethyl ammonium iodide also assumes tetragonal forms, but does not exhibit the cleavage of the tetramethyl compound; while tetrapropyl ammonium iodide crystallizes in rhombic form.
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  • In the combined state nitrogen is fairly widely distributed, being found in nitre, Chile saltpetre, ammonium salts and in various animal and vegetable tissues and liquids.
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  • In de Lambilly's process air and steam is led over white-hot coke, and carbon dioxide or monoxide removed from the escaping gases according as ammonium formate or carbonate is wanted.
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  • The reactions are represented as (I) N2+3H2+2C0 -1-2H 2 0=2H CO 2 NH 4 (Ammonium formate).
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  • Soon afterwards, William Cruickshank decomposed the magnesium, sodium and ammonium chlorides, and precipitated silver and copper from their solutions - an observation which led to the process of electroplating.
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  • The dissolved salts (potassium, sodium, ammonium, calcium, magnesium, &c.) of the latex are generally nearly entirely absent from the wellprepared rubber.
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  • Klaproth in the mineral honeystone, which is the aluminium salt of the acid, The acid may be prepared by warming honeystone with ammonium carbonate, boiling off the excess of the ammonium salt and adding ammonia to the solution.
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  • The precipitated alumina is filtered off, the filtrate evaporated and the ammonium salt of the acid purified by recrystallization.
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  • The ammonium salt is then converted into the lead salt by precipitation with lead acetate and the lead salt decomposed by sulphuretted hydrogen.
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  • The mixture may be separated by dissolving out the ammonium euchroate with water.
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  • Ammonium nitrate and nitrite, for instance, intensify the action of a water on lead.
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  • Heating or exposure to sunlight reduces it to the red oxide; it fires when ground with sulphur, and oxidizes ammonia to nitric acid, with the simultaneous formation of ammonium nitrate.
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  • 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.
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  • It is produced by the addition of a solution of lead salt to an excess of ammonium carbonate, as an almost insoluble white precipitate.
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  • Ammonium sulphide blackens it, and it is soluble in solution of ammonium acetate, which distinguishes it from barium sulphate.
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  • The inactive mixture may be resolved into its active components by fractional crystallization of the cinchonine salt, when the salt of the dextro modification separates first; or the ammonium salt may be fermented by Penicillium glaucum, when the laevo form is destroyed and the dextro form remains untouched; on the other' hand, Saccharomyces ellipsoideus destroys the dextro form, but does not touch the laevo form.
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  • Potash alum is the common alum of commerce, although both soda alum and ammonium alum are manufactured.
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  • It is now allowed to stand for some time, decanted from any sediment, and finally mixed with the calculated quantity of potassium sulphate (or if ammonium alum is required, with ammonium sulphate), well agitated, and the alum is thrown down as a finely-divided precipitate of alum meal.
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  • Columbium compounds are usually prepared by fusing columbite with an excess of acid potassium sulphate, boiling out the fused mass with much water, and removing tin and tungsten from the residue by digestion with ammonium sulphide, any iron present being simultaneously converted into ferrous sulphide.
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  • 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.).
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  • The precipitate, after having been collected and washed, is digested with a warm concentrated solution of ammonium carbonate, which dissolves the uranium as a yellow solution of ammonium uranate, while the hydrated oxide of iron, the alumina, &c., remain.
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  • The mother liquor includes generally more or less of nickel, cobalt, zinc and other heavy metals, which, as Wailer showed, can be removed as insoluble sulphides by the addition of ammonium sulphide; uranium, under the circumstances, is not precipitated by this reagent.
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  • Ammonium uranate heated to redness yields pure U308, which serves as a raw material for uranium compounds.
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  • Uranyl nitrate is used in photography, and also in analytical chemistry as a precipitant for phosphoric acid (as uranyl ammonium phosphate, U02 NH4 P04).
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  • Uranyl sulphide, UO 2 S, is a black precipitate obtained by adding ammonium sulphide to a uranyl solution.
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  • Stannous sulphide, SnS, is obtained as a lead-grey mass by heating tin with sulphur, and as a brown precipitate by adding sulphuretted hydrogen to a stannous solution; this is soluble in ammonium polysulphide, and dries to a black powder.
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  • Stannous salt solutions yield a brown precipitate of SnS with sulphuretted hydrogen, which is insoluble in cold dilute acids and in real sulphide of ammonium, (NH 4) 2 S; but the yellow, or the colourless reagent on addition of sulphur, dissolves the precipitate as SnS 2 salt.
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  • Stannic salt solutions give a yellow precipitate of SnS 2 with sulphuretted hydrogen, which is insoluble in cold dilute acids but readily soluble in sulphide of ammonium, and is re-precipitated therefrom as SnS2 on acidification.
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  • The nitrate of this base (known as nitron) is so insoluble that nitrates may be gravimetrically estimated with its help. These bases combine with the alkyl iodides to yield quaternary ammonium salts.
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  • Ammonium hydroxide has no appreciable action at ordinary temperatures, but strong solutions of sodium or potassium hydroxides start a decomposition, with rise of temperature, in which some nitrate and always some nitrite is produced.
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  • It appears that with soils which are not rich in humus or not deficient in lime, calcium cyanamide is almost as good, nitrogen for nitrogen, as ammonium sulphate or sodium nitrate; but it is of doubtful value with peaty soils or soils containing little lime, nor is it usefully available as a top-dressing or for storing.
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  • Iron, zinc, cadmium, also tin under certain conditions, reduce the dilute acid, partially at least, to nitrous oxide, N 2 0, or ammonium nitrate, NH4N03.
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  • In the first stage the ammonium compounds are oxidized to nitrites by the agency of very minute motile bacteria belonging to the genus Nitrosomonas.
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  • Zinc sulphate, like magnesium sulphate, unites with the sulphates of the potassium metals and of ammonium into crystalline double salts, ZnS04 R2S04-+-6H20, isomorphous with one another and the magnesium salts.
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  • 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.
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  • Titanium trioxide, T103, is obtained as a yellow precipitate by dropping the chloride into alcohol, adding hydrogen peroxide, and finally ammonium carbonate or potash.
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  • Acid solutions of titanates are not precipitated by sulphuretted hydrogen; but ammonium sulphide acts on them as if it were ammonia, the sulphuretted hydrogen being liberated.
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  • The tertiary amines possess the power of combining with one molecular proportion of an alkyl iodide to form quaternary ammonium salts.
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  • They are ionized in aqueous solution to a much greater extent than ammonia, the quaternary ammonium bases being the most ionized, and the secondary bases being more strongly ionized than the primary or tertiary bases.
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  • By the action of ammonia on the alkyl iodides a complex mixture of primary, secondary and tertiary amines, along with a quaternary ammonium salt, is obtained, the separation of which is difficult.
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  • If the nitrogen atom in the quaternary ammonium salts be in combination with four different groups, then the molecule is asymmetrical, and the salt can be resolved into optically active enantiamorphous isomerides.
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  • It is an amorphous solid, insoluble in water, but its solubility is increased in the presence of ammonium nitrate.
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  • It is found in the form of its acid potassium salt in many plants, especially in wood-sorrel (Oxalis acetosella) and in varieties of Rumex; as ammonium salt in guano; as calcium salt in rhubarb root, in various lichens and in plant cells; as sodium salt in species of Salicornia and as free acid in varieties of Boletus.
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  • The blackish brown sulphide precipitated from bismuth salts by sulphuretted hydrogen is insoluble in ammonium sulphide, but is readily dissolved by nitric acid.
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  • Recent limestones are being produced in this way and also in some places by the precipitation of calcium carbonate by sodium or ammonium carbonate which has been carried into the sea or formed by organisms. The precipitated carbonate may agglomerate on mineral or organic grains which serve as nuclei, or it may form a sheet of hard deposit on the bottom as occurs in the Red Sea, off Florida, and round many coral islands in the Pacific. Only the sand and the finest-grained sediments of the shore zone are carried outwards over the continental shelf by the tides or by the reaction-currents along the bottom set up by on-shore winds.
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  • They are mostly distinguished by special trade names, and are mainly of two classes - those containing ammonium nitrate and nitrobenzene or nitronaphthalene, and those containing nitroglycerin and nitrocellulose, which are essentially weak dynamites.
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  • Seubert (Ber., 1888, 21, p. 1839) from the analysis of potassium and ammonium osmichlorides, the values obtained being approximately 191.
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  • Zirconium fluoride, ZrF4, is obtained as glittering monoclinic tables (with 3H 2 0) by heating zirconia with acid ammonium fluoride.
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  • Metaphosphoric acid can be distinguished from the other two acids by its power of coagulating albumen, and by not being precipitated by mag nesium and ammonium chlorides in the presence of ammonia.
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  • Sulphuric acid gives a white precipitate of calcium sulphate with strong solutions; ammonium oxalate gives calcium oxalate, practically insoluble in water and dilute acetic acid, but readily soluble in nitric or hydrochloric acid.
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  • 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.
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  • Ammonium salts too are found distributed through all fertile soil, in sea-water, and in most plant and animal liquids, and also in urine.
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  • 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.
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  • Large quantities of ammonia and ammonium salts are now obtained from the ammoniacal liquor of gas-works.
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  • The aqueous solution of ammonia is very basic in its reactions, and since it is a weak electrolyte, one must assume the solution to contain a certain amount of ammonium hydroxide NH 4 OH, although it is probably chiefly composed of a solution of ammonia in water.
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  • The salts produced by the action of ammonia on acids are known as the ammonium salts and all contain the compound radical ammonium (NH 4).
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  • 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.
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  • Many of the ammonium salts are made from the ammoniacal liquor of gas-works, by heating it with milk of lime and then absorbing the gas so liberated in a suitable acid.
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  • Ammonium iodide, NH 4 I, can be prepared by the action of hydriodic acid on ammonia.
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  • Ammonium chlorate, NH 4 C10 3, is obtained by neutralizing chloric acid with either ammonia or ammonium carbonate, or by precipitating barium, strontium or calcium chlorates with ammonium carbonate.
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  • The commercial salt is known as salvolatile or salt of hartshorn and was formerly obtained by the dry distillation of nitrogenous organic matter such as hair, horn, decomposed urine, &c., but is now obtained by heating a mixture of sal-ammoniac, or ammonium sulphate and chalk, to redness in iron retorts, the vapours being condensed in leaden receivers.
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  • It possesses a strong ammoniacal smell, and on digestion with alcohol the carbamate is dissolved and a residue of ammonium bicarbonate is left; a similar decomposition taking place when the sesquicarbonate is exposed to air.
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  • Ammonium nitrate, NH 4 NO 3, is prepared by neutralizing nitric acid with ammonia, or ammonium carbonate, or by double decomposition between potassium nitrate and ammonium sulphate.
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  • 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.
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  • It is used largely as an artificial manure, and also for the preparation of other ammonium salts.
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  • Several complex polysulphides of ammonium have been isolated, for details of which see Bloxam's paper quoted above.
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  • Ammonia and ammonium salts can be readily detected, in very minute traces, by the addition of Nessler's solution, which gives a distinct yellow coloration in the presence of the least trace of ammonia or ammonium salts.
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  • 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.
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  • The solution of ammonium chloride so obtained is evaporated and the crude ammonium chloride purified by sublimation.
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  • Sal ammoniac (ammonium chloride, British and United States pharmacopoeiae) as used in medicine is a white crystalline odourless powder having a saline taste.
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  • Ammonium chloride has a different action and therapeutic use from the rest of the ammonium salts.
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  • The inhalation of the fumes of nascent ammonium chloride by filling the room with the gas has been recommended in foetid bronchitis.
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  • 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.
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  • It unites directly with ammonia gas to form ammonium carbamate, NH 2 00ONH 4.
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  • The most commonly used salt is the iodide of potassium; the iodides of sodium and ammonium are almost as frequently employed, and those of calcium and strontium are in occasional use.
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  • Another often successful method of preventing the onset of symptoms of poisoning is to administer small doses of ammonium carbonate with the drug, thereby neutralizing the iodic acid which is liberated in the stomach.
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  • The anhydrous acid combines with hydrochloric, hydrobromic and hydriodic acids to form crystalline addition products, which are decomposed by water with the formation of the corresponding ammonium salt and formic acid.
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  • Ammonium cyanide, NH 4 NC, a white solid found to some slight extent in illuminating gas, is easily soluble in water and alcohol, and is very poisonous.
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  • The potassium sulphocyanide is obtained from ammonium sulphocyanide, which is formed by washing crude coal gas with water containing suspended sulphur.
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  • As an alternative test the cyanide may be decomposed by dilute hydrochloric acid, and the liberated hydrocyanic acid absorbed in a little yellow ammonium sulphide.
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  • The silver and mercury salts, when heated, yield the metal, with liberation of carbon dioxide and formation of free formic acid; and the ammonium salt, when distilled, gives some formamide, Hconh 2.
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  • The sesquioxide, Cr 2 0 3, occurs native, and can be artificially obtained in several different ways, e.g., by igniting the corresponding hydroxide, or chromium trioxide, or ammonium bichromate, or by passing the vapours of chromium oxychloride through a red-hot tube, or by ignition of mercurous chromate.
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  • The hydrated fluoride, CrF3.9H20, obtained by adding ammonium fluoride to cold chromic sulphate solution, is sparingly soluble in water, and is decomposed by heat.
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  • Chromium ammonium sulphate, (NH4)2S04 Cr2(S04)3.24H20, results on mixing equivalent quantities of chromic sulphate and ammonium sulphate in aqueous solution and allowing the mixture to crystallize.
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  • By the action of concentrated sulphuric acid it is transformed into chromium ammonium sulphate.
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  • When reduced (in acid solution) they yield amines; distillation with reduced iron gives azo compounds, and warming with ammonium sulphide gives hydrazo compounds.
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  • The chromates of sodium, potassium and ammonium, as well as the bichromates of potassium and ammonium, were found to give the same absorption spectrum.
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  • Magnesium hydroxide is a white amorphous solid which is only slightly soluble in water; the solubility is, however, greatly increased by ammonium salts.
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  • 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.
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  • The solution is evaporated, and the residue strongly heated, when water and ammonium chloride are expelled, and anhydrous magnesium chloride remains.
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  • It is almost insoluble in water, but readily dissolves in ammonium salts.
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  • Magnesium ammonium phosphate, MgNH 4 PO 4.6H 2 O, is found as the mineral struvite and in some guanos; it occurs also in urinary calculi and is formed in the putrefaction of urine.
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  • It is prepared by adding sodium phosphate to magnesium sulphate in the presence of ammonia and ammonium chloride.
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  • 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.
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  • The same reaction is made use of in the quantitative determination of magnesium, the white precipitate of magnesium ammonium phosphate being converted by ignition into magnesium pyrophosphate and weighed as such.
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  • Whatever were the means employed to rid air of accompanying oxygen, a uniform value of the density was arrived at, and this value was z% greater than that appertaining to nitrogen extracted from compounds such as nitrous oxide, ammonia and ammonium nitrite.
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  • In the earlier stages of the inquiry, when it was important to meet the doubts which had been expressed as to the presence of the new gas in the atmosphere, blank experiments were executed in which air was replaced by nitrogen from ammonium nitrite.
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  • It attacks most metals readily, usually with production of a nitrate or hydrated oxide of the metal and one or other of the oxides of nitrogen, or occasionally with the production of ammonium salts; magnesium, however, liberates hydrogen from the very dilute acid.
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  • 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.
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  • 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.
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  • Hantzsch, Ber., This assumption also shows the relationship of the diazonium hydroxides to other quaternary ammonium compounds, for most of the quaternary ammonium hydroxides (except such as have the nitrogen atom attached to four saturated hydrocarbon radicals) are unstable, and readily pass over into compounds in which the hydroxyl group is no longer attached to the amine nitrogen; thus the syn-diazo hydroxides are to be regarded as pseudo-diazonium derivatives.
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  • Hydrogen may also be obtained by the action of zinc on ammonium salts (the nitrate excepted) (Lorin, Comptes rendus, 1865, 60, p. 745) and by heating the alkali formates or oxalates with caustic potash or soda, Na2C204+2NaOH = H 2 +2Na 2 CO 3.
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  • The study of polymorphism has been especially pursued by Otto Lehmann, who proved that it is an almost general property; the variety of forms which a given substance may show is often great, ammonium nitrate, for instance, showing at least four of them before melting.
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  • 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.
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  • It decomposes ammonium salts.
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  • This is now treated for some days with a hot concentrated solution of ammonium carbonate, which precipitates the iron and aluminium but keeps the beryllium in solution.
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  • To remove the iron, the precipitate is again dissolved in ammonium carbonate and steam is blown through the liquid, when beryllium oxide is precipitated.
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  • Beryllium salts are easily soluble and mostly have a sweetish taste (hence the name Glucinum, from yXv,dc, sweet); they are readily precipitated by alkaline sulphides with formation of the white hydroxide, and may be distinguished from salts of all other metals by the solubility of the oxide in ammonium carbonate.
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  • In organic chemistry he published papers on the decomposition of ammonium oxalate, with formation of oxamic acid, on amyl alcohol, on the cyanides, and on the difference in constitution between nitric and sulphuric ether.
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  • Sulphuretted hydrogen, in the presence of free mineral acid, gives no precipitate; sulphide of ammonium, from neutral solutions, precipitates T12S as a dark brown or black precipitate, insoluble in excess of reagent.
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  • Dry chlorine gas passed into melted urea decomposes it with formation of cyanuric acid and ammonium chloride, nitrogen and ammonia being simultaneously liberated.
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  • Benzamide, C 6 H 5 CONH 2, is prepared by the action of benzoyl chloride on ammonia or ammonium carbonate, or from ethyl benzoate and ammonia.
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  • Benzoic acid itself, ammonium benzoate and sodium benzoate are all administered internally in doses of from five to thirty grains.
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  • The ammonium salt is most often employed, owing to the stimulant character of the ammonium base.
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  • Ammonium sulphide alone gives incomplete precipitation of the sulphide.
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  • In the presence of ammonium salts the precipitate is dirt y white in colour, whilst in the presence of free ammonia it is a buff colour.
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  • It may be obtained synthetically by the action of ammonium iodide on cyanamide, CN NH2+ NH 4 I=CN 3 H 5 HI
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  • Many hydrated forms of the sulphate are known, as are also double salts of the sulphate with potassium, sodium, ammonium, thallium and cadmium sulphates.
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  • It begins, however, not with ready-made ammonium bicarbonate, but with the substances from which it is formed - ammonia, water and carbon dioxide - which are made to act on sodium chloride.
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  • The ammonia is for the major part found in the mother-liquor as ammonium chloride.
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  • A smaller but still considerable portion exists here and in the washings in the shape of ammonium carbonates.
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  • The steam causes the action of the lime on the ammonium chloride to take place in this lower portion of the still, from which the steam, mixed with all the liberated ammonia, rises into the upper portion of the column where its heat serves to drive out the volatile ammonium carbonate.
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  • Ammonium sulphide precipitates black nickel sulphide, which is somewhat soluble in excess of the precipitate (especially if yellow ammonium sulphide be used), forming a dark-coloured solution.
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  • Ammonium hydroxide gives a green precipitate of the hydroxide, soluble in excess of ammonia, forming a blue solution.
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  • Rubidium carbonate, Rb2C03, formed by the addition of ammonium carbonate to rubidium hydroxide, is a crystalline mass which melts in its water of crystallization when heated.
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  • Several other sodium tungstates are known, as well as potassium and ammonium tungstates.
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  • On boiling gelatinous silica with ammonium polytungstate and evaporating with the occasional addition of ammonia, ammonium silicodecitungstate is obtained as short rhombic prisms. On adding silver nitrate and decomposing the precipitated silver salt with hydrochloric acid, a solution is obtained which on evaporation in a vacuum gives the free acid as a glassy mass.
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  • The trisulphide, WS3, is obtained by dissolving the trioxide in ammonium sulphide or by passing sulphuretted hydrogen into a solution of a tungstate and precipitating by an acid in both cases.
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  • His method consisted in using magnesia instead of lime for the recovery of the ammonia (which occurs in the form of ammonium chloride in the ammonia-soda process), and then by evaporating the magnesium chloride solution and heating the residue in steam, to condense the acid vapours and so obtain hydrochloric acid.
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  • In this process the ammonium chloride is volatilized in large iron retorts lined with Doulton tiles, and then led into large upright wrought-iron cylinders lined with fire-bricks.
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  • It is usually obtained by the distillation of amber, or by the fermentation of calcium malate or ammonium tartrate.
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  • Heated in a current of ammonia it gives succinimide, which is also obtained on heating acid ammonium succinate.
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  • A purer product is obtained by adding ammonium chloride, filtering, and washing with hot water.
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  • The more important picric powders are melinite, believed to be a mixture of fused picric acid and gun-cotton; lyddite, the British service explosive, and shimose, the Japanese powder, both supposed to be identical with the original melinite; Brugere's powder, a mixture of 54 parts of ammonium picrate and 45 parts of saltpetre; Designolle's powder, composed of potassium picrate, saltpetre and charcoal; and emmensite, invented by Stephen Emmens, of the United States.
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  • The sodium ammonium salt is not capable of decomposition into its optical antipodes, as is sodium ammonium racemate.
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  • Barium carbonate, BaCO 31 occurs rather widely distributed as witherite, and may be prepared by the addition of barium chloride to a hot solution of ammonium carbonate, when it is precipitated as a dense white powder of specific gravity 4.3; almost insoluble in water.
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  • Many forms in rivers, soil, manure heaps, &c., are capable of bringing about this change to ammonium carbonate, and much of the loss of volatile ammonia on farms is preventible if the facts are apprehended.
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  • As regards the ammonium carbonate accumulating in the soil from the conversion of urea and other sources, we know from Winogradsky's researches that it undergoes oxidation in two stages owing to the activity of the so-called " nitrifying " bacteria (an unfortunate term inasmuch as " nitrification " refers merely to a particular phase of the cycle of changes undergone by nitrogen).
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  • It has been suggested that urea is formed by polymerization of ammonium carbonate, and formic aldehyde is synthesized from CO 2 and 011 2.
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  • The Nitro-bacteria are smaller, finer and quite different from the nitroso-bacteria, and are incapable of attacking and utilizing ammonium carbonate.
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  • The insoluble matter is treated with a hot solution of alkaline ammonium acetate, which dissolves the lead sulphate, the other materials being separated by filtration.
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  • There are several volumetric methods for assaying lead ores, but the best known is that based on the precipitation of lead by ammonium molybdate in an acetic acid solution.
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  • The lead sulphate, obtained as described above and dissolved in ammonium acetate, is acidulated with acetic acid diluted with hot water and heated to boiling-point.
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  • A standardized solution of ammonium molybdate is then added from a burette.
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  • It is standardized by dissolving a weighed amount of lead sulphate in ammonium acetate and proceeding as described above.
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  • It is then heated with a mixture of ammonium chloride and ammonia, filtered and washed with a hot dilute solution of the same mixture.
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  • The ferrocyanide solution is standardized by dissolving i gramme of pure zinc in 6 cc. of hydrochloric acid, adding ammonium chloride, and titrating as before.
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  • Ammonium Ferrous Sulphate May Also Be Used; It Contains One Seventh Of Its Weight Of Iron.
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  • The filtered (blue) solution is now mixed with an excess of solution of ammonium sulphite, and allowed to stand.
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  • Its solubility in water is lessened by sodium or magnesium sulphate, but is increased by potassium nitrate, ammonium chloride, and most acids.
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  • In medicine it is largely employed in the form of bromides of potassium, sodium and ammonium, as well as in combination with alkaloids and other substances.
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  • In whooping-cough, when a sedative is required but a stimulant is also indicated, ammonium bromide is often invaluable.
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  • Ammonia also reacts immediately, giving phosphorus diamide, P(OH)(NH2)2, and the corresponding ammonium salt.
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  • With dry ammonia it gives ammonium fluoride and a compound P(NH2)2SF.
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  • Nitrogen Compounds.-Phosphorus pentachloride combines directly with ammonia, and the compound when heated to redness loses ammonium chloride and hydrochloric acid and gives phospham, PN 2 H 4, a substance first described by Davy in 1811.
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  • This latter compound readily forms an iodmethylate, which on treatment with silver oxide yields the corresponding ammonium hydroxide.
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  • It forms small hard prisms which become red on exposure to air containing ammonia, owing to the formation of murexide (ammonium purpurate),C $ 11 4 (NH 4)N 5 0 6.
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  • The most important of these is sulphate of ammonia, which is used for agricultural purposes as a manure, and is obtained by passing ammonia into sulphuric acid and crystallizing out the ammonium sulphate produced.
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  • To do this, saturated ammoniacal liquor is decomposed by lime in the presence of steam, and the freed ammonia is passed into strong sulphuric acid, the saturated solution of ammonium sulphate being carefully crystallized.
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  • This liquid is a strong solution of ammonium sulphate, containing about 2 5% free sulphuric acid which absorbs nearly all the ammonia from the gases, without dissolving much of the tarry substances.
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  • Most of the liquor arriving at the bottom, after mechanically separating the tar, is pumped back into s, but a portion is always withdrawn and worked for ammonium sulphate.
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  • The yield of ammonium sulphate is 75 lb from a ton of coal (slack with 11.5% ashes and 55% fixed carbon).
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  • It dissolves in dilute cold nitric acid with the formation of ferrous and ammonium nitrates, no gases being liberated; when heated or with stronger acid ferric nitrate is formed with evolution of nitrogen oxides.
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  • It absorbs ammonia gas, forming the compound FeC12.6NH31 which on heating loses ammonia, and, finally, yields ammonium chloride, nitrogen and iron nitride.
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  • By adding ammonium chloride to the solution, evaporating in vacuo, and then volatilizing the ammonium chloride, anhydrous ferrous chloride is obtained.
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  • Another black amorphous form results when ferrous salts are precipitated by ammonium sulphide.
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  • It is also prepared by precipitating a ferric salt with ammonium sulphide; unless the alkali be in excess a mixture of ferrous sulphide and sulphur is obtained.
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  • The most important is ferrous ammonium sulphate, FeS04(NH4)2S04,6H20, obtained by dissolving equivalent amounts of the two salts in water and crystallizing.
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  • It oxidizes on heating in air, and ignites in chlorine; on solution in mineral acids it yields ferrous and ammonium salts, hydrogen being liberated.
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  • Ferric nitrate, Fe(NO3) 3, is obtained by dissolving iron in nitric acid (the cold dilute acid leads to the formation of ferrous and ammonium nitrates) and crystallizing, when cubes of Fe(NO3)3.6H20 or monoclinic crystals of Fe(N03)3.9H20 are obtained.
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  • The heptanitroso acid is precipitated as a brown amorphous mass by dilute sulphuric acid, but if the salt be heated with strong acid it yields nitrogen, nitric oxide, sulphur, sulphuretted hydrogen, and ferric, ammonium and potassium sulphates.
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  • The residue is extracted by absolute alcohol, which dissolves the hydroxylamine hydrochloride and a little ammonium chloride; this last substance is removed as ammonium platinochloride, and the residual hydroxylamine hydrochloride is recrystallized.
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  • Vanadium salts may be obtained from mottramite by digesting the mineral with concentrated hydrochloric acid, the liquid being run off and the residue well washed; the acid liquid and the washings are then evaporated with ammonium chloride, when ammonium metavanadate separates.
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  • This is recrystallized and roasted to vanadium pentoxide, which is then suspended in water into which ammonia is passed, when ammonium metavanadate is again formed and may be purified by recrystallization.
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  • The trioxide, V 2 0 3, is formed when the pentoxide is reduced at a red heat in a current of hydrogen, or by the action of oxalic acid on ammonium metavanadate.
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  • The pentoxide, V205, is obtained when ammonium metavanadate is strongly heated, on calcining the sulphide, or by the decomposition of vanadyl trichloride with water.
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  • Ammonium metavanadate is obtained when the hydrated vanadium pentoxide is dissolved in excess of ammonia and the solution concentrated.
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  • Gain (Comptes rendus, 1906, 1 43, p. 823) by calcining ammonium metavanadate and saturating a solution of the resulting oxides with sulphur dioxide; the resulting blue solution (from which a sulphate of composition 2V 2 0 4.3S0 2.10H 2 O can be isolated) is then boiled with water, when sulphur dioxide is liberated and a pale red crystalline powder of hypovanadic acid, H4V205, is precipitated.
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  • In the wet way, arsenious oxide and arsenites, acidified with hydrochloric acid, give a yellow precipitate of arsenic trisulphide on the addition of sulphuretted hydrogen; this precipitate is soluble in solutions of the alkaline hydroxides, ammonium carbonate and yellow ammonium sulphide.
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  • The salts of arsenic acid, termed arsenates, are isomorphous with the phosphates, and in general character and reactions resemble the phosphates very closely; thus both series of salts give similar precipitates with "magnesia mixture" and with ammonium molybdate solution, but they can be distinguished by their behaviour with silver nitrate solution, arsenates giving a reddish-brown precipitate,whilst phosphates give a yellow precipitate.
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  • Ten volumes of the purest coal-tar benzene were shaken for four hours with one volume of sulphuric acid, the acid layer was removed and neutralized with lead carbonate, and the lead thiophen sulphonate obtained was distilled with an equivalent quantity of ammonium chloride.
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  • The distillate obtained was diluted with one hundred volumes of ligroin (previously purified by shaking with fuming sulphuric acid) and then shaken for one or two hours with sulphuric acid (using ten volumes of acid to one volume of the distillate), the acid layer diluted with water, neutralized by lead carbonate and the lead salt again distilled with an equivalent quantity of ammonium chloride.
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  • Hydrolysis by means of acids or alkalis converts the asparagines into aspartic acid; whilst on heating with water in a sealed tube they are converted into ammonium aspartate.
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  • They are readily decomposed by heat, leaving a residue of the normal chromate and chromium sesquioxide, and liberating oxygen; ammonium bichromate, however, is completely decomposed into chromium sesquioxide, water and nitrogen.
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  • Similar sodium, ammonium, lithium, magnesium, calcium, barium and zinc salts have been obtained.
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  • An indium ammonium alum, In2(S04)3 (NH4)2S04.24H20 is known.
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  • Potassium and lithium have a depressing action upon the nervous system, ammonium salts have a stimulating action, while sodium practically speaking is indifferent.
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  • Sodium nitrate, potassium nitrate, potassium chloride, ammonium chloride, the alkaline iodides and bromides, also belong partly to this group, although most of them have also specific actions.
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  • Part of it only is soluble in water, and that resembles gummic acid in being precipitated by alcohol and ammonium oxalate, but differs from it in giving a precipitate with neutral lead acetate and none with borax.
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  • To the alcoholic solution, four times its volume of ether is added, when the ammonium salt is precipitated.
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  • Crystal deodorant is a naturally occurring crystal of pure ammonium alum.
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  • Then the hydrogen chloride produced reacts with excess ammonia to give ammonium chloride.
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  • The GM beet was tolerant to glyphosate, the GM maize and oilseed rape were tolerant to glufosinate ammonium.
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  • Nitrogen accumulation methods include measurement of plant tissue N concentration, amino acids, substrate N and foliar ammonium.
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  • It contributes between 10% to 40% to the total ammonium deposited on the central Greenland ice sheet during the Holocene.
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  • The sum of ammonia and particulate ammonium (total inorganic ammonium, TIA) is also to be measured daily at these sites.
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  • The ammonium ion together with the chloride ion formed in the previous stage makes up the ammonium chloride produced in the reaction.
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  • To enable efficacy and demonstration work to be conducted with the herbicide glufosinate- ammonium.
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  • The second most common type, accounting for 6-20% of renal stones, is formed from struvite (magnesium ammonium phosphate ).
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  • The plasma ammonium level reached a plateau of approximately 400 m mol/l at 100 watts.
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  • Diffusion rates vary between nutrients (nitrate ammonium phosphate ).
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  • On heating strongly, the white solid ammonium chloride, decomposes into a mixture of two colorless gases - ammonia and hydrogen chloride.
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  • Ammonia (NH 3) also dissolves in water to produce an ammonium hydroxide (NH 4 OH ), an alkaline solution.
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  • The leaflet offers some practical help and guidance for sites, such as quarries, that use ammonium nitrate for blasting.
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  • The reaction required heating ammonium nitrate and was quite simple in nature.
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  • Process 1. Dissolve gum arabic in water and mix it with a pigment and a solution of potassium bichromate or ammonium bichromate.
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  • For example, ammonia reacts with HBr to give ammonium bromide, NH 4 + Br - .
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  • Both experimental work and ab-initio calculations agree that the most stable form is the ammonium ion pair species.
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  • In 1870 urea was produced by heating ammonium carbamate in a sealed vessel.
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  • One grower sprayed with copper ammonium carbonate against the disease.
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  • The ammonium ion together with the chloride ion formed in the previous stage makes up the ammonium chloride ion formed in the previous stage makes up the ammonium chloride produced in the reaction.
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  • Citrate - ferric ammonium citrate - ferric ammonium citrate - iron deficiency Nux vomica - stimulant of gastrointestinal tract, increase appetite.
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  • The ammonium salts do not sublime, really; they thermally dissociate into substances that recombine to the ammonium compound on cooling.
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  • Glutamine is readily synthesized from glutamate and ammonium ions by the enzyme glutamine is readily synthesized from glutamate and ammonium ions by the enzyme glutamine synthetase.
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  • An intermediate level of ammonium hydrosulfide is 60 km (37 miles) below that.
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  • Unfortunately, not everyone has access to ACS grade ammonium hydroxide.
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  • An ammonium ion is formed, together with an amine.
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  • The original rat monoclonal antibodies had been prepared from ascitic fluid, crudely fractionated with ammonium sulfate.
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  • Inside was half a ton of ammonium nitrate, an easy to buy fertilizer, the same material used in the Bali bombings.
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  • It was also decided to immerse one sample directly into the ammonium oxalate solution for five hours.
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  • In addition, Iraqi attempts to buy ammonium perchlorate, an oxidiser for solid propellant missiles, were successful, at least on paper.
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  • Ammoniacal nitrogen may increase blossom-end rot as excess ammonium ions reduce calcium uptake.
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  • Glutamine is readily synthesized from glutamate and ammonium ions by the enzyme glutamine synthetase.
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  • Iran has acknowledged the production of uranium metal, uranyl nitrate, ammonium uranyl carbonate, UO2 pellets and uranium wastes.
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  • The iridium is then precipitated from the solution (as oxide) by the addition of baryta, dissolved in aqua regia, and precipitated as iridium ammonium chloride by the addition of ammonium chloride.
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  • The corresponding hydroxide, Ir(OH) 4, is formed when potassium iridate is boiled with ammonium chloride, or when the tetrachloride is boiled with caustic potash or sodium carbonate.
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  • Berglund (Berichte, 18 74, 7, p. 469), in aqueous solution, by dissolving ammonium cobaltocobaltisulphite (NH4)2C02 [(S03) 6 'C02] 14H 2 O in dilute hydrochloric or nitric acids, or by decomposition of its silver salt with hydrochloric acid.
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  • The diammine salts are prepared by the action of alkaline nitrites on cobaltous salts in the presence of much ammonium chloride or nitrate; they are yellow or brown crystalline solids, not very soluble in cold water.
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  • Thus, Pasteur showed that Penicillium glaucum, when grown in an aqueous solution of ammonium racemate, decomposed the dextro-tartrate, leaving the laevotartrate, and the solution which was originally inactive to polarized light became dextro-rotatory.
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  • It is now known that the action takes place in two stages; the ammonium salt is first oxidized to the nitrite stage and subsequently to the nitrate.
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  • In many parts, particularly in the eastern basin, a calcareous or siliceous crust, from half an inch to three inches in thickness, is met with; and Natterer suggested that the formation of this crust may be due to the production of carbonate of ammonium where deposits containing organic matter are undergoing oxidation, and the consequent precipitation of carbonate of lime and other substances from the waters nearer the surface.
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  • It dissolves readily in water and the aqueous solution decomposes on standing; a dark-brown flocculent precipitate of azulmic acid, C 4 H 5 N 5 0, separating whilst ammonium oxalate, urea and hydrocyanic acid are found in the solution.
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  • Jackson patented the preparation of ammonium oleate directly in the washing water, and it is claimed that for cleansing articles it is only necessary to immerse them in the water containing the preparation and then rinse.
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  • The precipitate is shaken with ammonium carbonate, which dissolves the arsenic. Filter and confirm arsenic in the solution by its particular tests.
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  • The urea in urine is also rapidly converted by the uro-bacteria into ammonium carbonate.
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  • His perception of the analogy between it and ammonia led to his famous work on the amines and ammonium bases and the allied organic phosphorus compounds, while his researches on rosaniline, which he first prepared in 1858, formed the first of a series of investigations on colouring matters which only ended with quinoline red in 1887.
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  • But the most important fact is that ammonium benzoate is largely used - often in combination with urinary anodynes such as tincture of hyoscyamus - as a urinary antiseptic in cases of cystitis (inflammation of the bladder) and pyelitis (inflammation of the pelvis of the kidney).
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  • By the early twentieth century, most manufacturing of fertilizer had switched to the synthetic production of ammonium sulfate and ammonium phosphate.
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  • Care should be taken using quaternary ammonium compounds in soft water.
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  • To get mainly the quaternary ammonium salt, you can use a large excess of bromoethane.
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  • For example, if you titrate ammonia solution with hydrochloric acid, you would get ammonium chloride formed.
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  • Manufacturers treat it with a number of fire retardant chemicals that are considered effective and safe, however, like sodium borate, boric acid, and ammonium sulfate.
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  • In a similar way potassium and ammonium cobalt alums have been obtained.
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  • The ammonium cobalto-cobaltisulphite is prepared by saturating an air-oxidized ammoniacal solution of cobaltous chloride with sulphur dioxide.
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  • This precipitate is insoluble in cold dilute acids, in ammonium sulphide, and in solutions of the caustic alkalis," a behaviour which distinguishes it from the yellow sulphides of arsenic and tin.
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  • Of these iron and ammonium citrate is much used as a haematinic, and as it has hardly any tendency to cause gastric irritation or constipation it can be taken when the ordinary forms of iron are inadmissible.
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  • When passed with carbon dioxide through a red-hot tube it yields carbon oxysulphide, COS (C. Winkler), and when passed over sodamide it yields ammonium thiocyanate.
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  • 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.
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  • A similar ammonium salt has been obtained.
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  • Salts of ammonium were also known; while alum was used as a mordant in dyeing.
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  • Among the Arabian and later alchemists we find attempts made to collate compounds by specific properties, and it is to these writers that we are mainly indebted for such terms as "alkali," " sal," &c. The mineral acids, hydrochloric, nitric and sulphuric acids, and also aqua regia (a mixture of hydrochloric and nitric acids) were discovered, and the vitriols, alum, saltpetre, sal-ammoniac, ammonium carbonate, silver nitrate (lunar caustic) became better known.
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  • In particular, the salts of potassium, sodium and ammonium were carefully investigated, but sodium and potassium salts were rarely differentiated.
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  • The solution is filtered off, boiled till free of sulphuretted hydrogen, and ammonium chloride and ammonia added.
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  • In this case, the precipitate is dissolved in as little as possible hydrochloric acid and boiled with ammonium acetate, acetic acid and ferric chloride.
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  • To the filtrate from the aluminium, iron and chromium precipitate, ammonia and ammonium sulphide are added; the precipitate may contain nickel, cobalt, zinc and manganese sulphides.
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  • Ammonium carbonate is added to the filtrate; this precipitates calcium, strontium and barium.
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  • The precipitate formed by sulphuretted hydrogen may contain the black mercuric, lead, and copper sulphides, dark-brown bismuth sulphide, yellow cadmium and arsenious sulphides, orange-red antimony sulphide, brown stannous sulphide, dull-yellow stannic sulphide, and whitish sulphur, the last resulting from the oxidation of sulphuretted hydrogen by ferric salts, chromates, &c. Warming with ammonium sulphide dissolves out the arsenic, antimony and tin salts, which are reprecipitated by the addition of hydrochloric acid to the ammonium sulphide solution.
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  • The residue from the ammonium sulphide solution is warmed with dilute nitric acid.
    1
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  • Treatment with casutic soda dissolves out aluminium hydroxide, which is reprecipitated by the addition of ammonium chloride.
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  • The solution with ammonium sulphide gives a white precipitate of zinc sulphide.
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  • The solution free from barium is treated with ammonia and ammonium sulphate, which precipitates strontium, and the calcium in the solution may be identified by the white precipitate with ammonium oxalate.
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  • The first class includes those substances which require no preliminary treatment, and comprises the amides and ammonium compounds, pyridines, quinolines, alkaloids, albumens and related bodies; the second class requires preliminary treatment and comprises, with few exceptions, the nitro-, nitroso-, azo-, diazoand amidoazo-compounds, hydrazines, derivatives of nitric and nitrous acids, and probably cyanogen compounds.
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