Phosphorus Sentence Examples

It may also be obtained by distilling nitric acid over phosphorus pentoxide.

Nuclein is a complex albuminoid substance containing phosphorus and iron in organic combination (Macallum).

For rails of basic open-hearth steel, which is rapidly ousting Bessemer steel, the Civil Engineers' specifications allowed from o 65 to 0-75% of carbon with 0-05% of phosphorus, while the specifications of the American Railway Engineering and Maintenance of Way Association provided for a range of 0.75 to 0-85% of carbon, with a maximum of 0.03% of phosphorus.

The molybdates are also capable of combining with other oxides (such as phosphorus and arsenic pentoxides) yielding very complex salts.

It is a good solvent for sulphur, phosphorus, wax, iodine, &c. It dissociates when heated to a sufficiently high temperature.

He burned phosphorus in air standing over mercury, and showed that (1) there was a limit to the amount of phosphorus which could be burned in the confined air, (2) that when no more phosphorus could be burned, one-fifth of the air had disappeared, (3) that the weight of the air lost was nearly equal to the difference in the weights of the white solid produced and the phosphorus burned, (4) that the density of the residual air was less than that of ordinary air.

In 1845 a further contribution to the study of allotropy was made by Anton Schrotter, who investigated the transformations of yellow and red phosphorus, phenomena previously noticed by Berzelius, the inventor of the term " allotropy."

Thus, the symbols 14 2 and P4 indicate that the molecules of hydrogen and phosphorus respectively contain 2 and 4 atoms. Since, according to the molecular theory, in all cases of chemical change the action is between molecules, such symbols as these ought always to be employed.

Of the halogen compounds of phosphorus, the trichloride was discovered by Gay Lussac and Thenard, while the pentachloride was obtained by Davy.

Theoretical speculations were revived by Lavoisier, who, having explained the nature of combustion and determined methods for analysing compounds, concluded that vegetable substances ordinarily contained carbon, hydrogen and oxygen, while animal substances generally contained, in addition to these elements, nitrogen, and sometimes phosphorus and sulphur.

Hence phosphorus cannot be removed in an acid-lined converter.

Pollution tests often include tests for naturally occurring chemicals like nitrates and phosphorus, as well as heavy metals like lead and mercury.

The true nitrile of malonic acid is methylene cyanide, CH 2 (CN) 2, which is obtained by distilling a mixture of cyanacetamide and phosphorus pentoxide.

The oxychloride, bromides, and other compounds were subsequently discovered; here we need only notice Moissan's preparation of the trifluoride and Thorpe's discovery of the pentafluoride, a compound of especial note, for it volatilizes unchanged, giving a vapour of normal density and so demonstrating the stability of a pentavalent phosphorus compound (the pentachloride and pentabromide dissociate into a molecule of the halogen element and phosphorus trichoride).

Nascent hydrogen reduces them to primary alcohols, and phosphorus pentachloride replaces the carbonyl oxygen by chlorine.

It has a strong and characteristic odour, and a hot sweetish taste, is soluble in ten parts of water, and in all proportions in alcohol, and dissolves bromine, iodine, and, in small quantities, sulphur and phosphorus, also the volatile oils, most fatty and resinous substances, guncotton, caoutchouc and certain of the vegetable alkaloids.

It behaves as a strong acid and on treatment with phosphorus pentachloride at high temperatures gives triazole.

Over and above the bacterial intoxications we have a very extreme degree of fatty degeneration, widely distributed throughout the tissues, which is produced by certain organic and inorganic poisons; it is seen especially in phosphorus and chloroform poisoning.

By heating with phosphorus pentachloride an alkyl group is eliminated and a chlorcarbonic ester formed.

According to Abel, the most favourable effect is produced by from I to 12% of phosphorus.

It is an excellent solvent for gums, resins, fats, &c.; sulphur, phosphorus and iodine also dissolve in it.

It has been found by experiment that plants need for their nutritive process and their growth, certain chemical elements, namely, carbon, hydrogen, oxygen, nitrogen, sulphur, phosphorus, potassium, magnesium, calcium and iron.

The sulphur exists in the soil chiefly in the form of sulphates of magnesium, calcium and other metals; the phosphorus mainly as phosphates of calcium, magnesium and iron; the potash, soda and other bases as silicates and nitrates; calcium and magnesium carbonates are also common constituents of many soils.

Rejecting the old notion that plants derive their nourishment from humus, he taught that they get carbon and nitrogen from the carbon dioxide and ammonia present in the atmosphere, these compounds being returned by them to the atmosphere by the processes of putrefaction and fermentation - which latter he regarded as essentially chemical in nature - while their potash, soda, lime, sulphur, phosphorus, &c., come from the soil.

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.

Calcium carbide, graphite, phosphorus and carborundum are now extensively manufactured by the operations outlined above.

By the action of sodium amalgam on an alcoholic solution of anthracene, an anthracene dihydride, C14H12, is obtained, whilst by the use of stronger reducing agents, such as hydriodic acid and amorphous phosphorus, hydrides of composition C14H16 and C14H24 are produced.

Braun (Ber., 1904, 37, p. 35 8 3) has prepared pentamethylene derivatives from piperidine by the action of phosphorus pentachloride.

Phosphorus pentachloride decomposes it into carbon monoxide and dioxide, the reaction being the one generally applied for the purpose of preparing phosphorus oxychloride.

When heated with phosphorus pentoxide it yields cyanogen.

Iron and phosphorus unite to form a solid solution which breaks up on cooling into a pearlite.

Kunkel shares with Boyle the honour of having discovered the secret of the process by which Brand of Hamburg had prepared phosphorus in 1669, and he found how to make artificial ruby (red glass) by the incorporation of purple of Cassius.

Under the same conditions it becomes incandescent in the vapour of sulphur, yielding calcium sulphide and carbon disulphide; the vapour of phosphorus will also unite with it at a red heat.

As stated under Phosphorus, phosphoric oxide, P 2 0 5, combines with water in three proportions to form H 2 O P 2 0 5 or HP03, metaphosphoric acid; 2H 2 O P 2 0 5 or H4P207, pyrophosphoric acid; and 3H 2 O P 2 0 5 or H 3 PO 4, orthophosphoric or ordinary phosphoric acid.

Orthophosphoric acid, H3P04, a tribasic acid, is obtained by boiling a solution of the pentoxide in water; by oxidizing, red phosphorus with nitric acid, or yellow phosphorus under the surface of water by bromine or iodine; and also by decomposing a mineral phosphate with sulphuric acid.

If the heating be with charcoal, the trimetallic salts of the alkalis and alkaline earths are unaltered, whilst the monoand di-salts give free phosphorus and a trimetallic salt.

The acid is formed by dissolving phosphorus pentoxide in cold water, or by strongly heating orthophosphoric acid.

The anhydrous nitrate, obtained by heating the crystallized salt, is very phosphorescent, and constitutes "Baldwin's phosphorus."

Calcium phosphide, Ca 3 P 2, is obtained as a reddish substance by passing phosphorus vapour over strongly heated lime.

It is particularly noteworthy from the phosphorescence which it exhibits when heated, or after exposure to the sun's rays; hence its synonym "Canton's phosphorus," after John Canton (1718-1772), an English natural philosopher.

From sodium phosphate are made sodii phosphas effervescens and sodii hypophosphis (see Phosphorus).

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.

A violent reaction ensues with phosphorus and sulphur, and many metals are oxidized by it, some with incandescence.

The best soils are the alluvium in the bottom-lands along some of the larger rivers and that of the Blue Grass Region, which is derived from a limestone rich in organic matter (containing phosphorus) and rapidly decomposing.

As a rule it is preferable to use iodine in the presence of a carrier, such as amorphous phosphorus or ferrous iodide or to use it with a solvent.

The usual method is to make a mixture of amorphous phosphorus and a large excess of iodine and then to allow water to drop slowly upon it; the reaction starts readily, and the gas obtained can be freed from any admixed iodine vapour by passing it through a tube containing some amorphous phosphorus.

It is a powerful reducing agent, and is frequently employed for this purpose in organic chemistry; thus hydroxy acids are readily reduced on heating with the concentrated acid, and nitro compounds are reduced to amino compounds, &c. It is preferable to use the acid in the presence of amorphous phosphorus, for the iodine liberated during the reduction is then utilized in forming more hydriodic acid, and consequently the original amount of acid goes much further.

The trichloride, IC1 31 results from the action of excess of chlorine on iodine, or from iodic acid and hydrochloric acid, or by heating iodine pentoxide with phosphorus pentachloride.

It dissolves iodine and absorbs chlorine, and is decomposed by water with formation of chromic and hydrochloric acids; it takes fire in contact with sulphur, ammonia, alcohol, &c., and explodes in contact with phosphorus; it also acts as a powerful oxidizing agent.

Duppa (Annalen, 1865, 136, p. 12) by acting with phosphorus pentachloride on oxyisobutyric ester (CH 3) 2 C(OH) 000C 2 H 5.

The same law prescribes conditions under which children between fourteen and eighteen years of age may be employed in the manufacture of white-lead, red-lead, paints, phosphorus, poisonous acids, tobacco or cigars, in mercantile establishments, stores, hotels, offices or in other places requiring protection to their health or safety; and it forbids the employment of boys under sixteen years of age or of girls under eighteen years of age in such factories or establishments more than ten hours a day (unless it be to prepare for a short day) or for more than fifty-eight hours to be chosen for the same term of service each voter shall vote for one only, and when three are to be chosen he shall vote for no more than two; candidates highest in vote shall be declared elected."

Conspicuous examples are afforded by oxygen, carbon, boron, silicon, phosphorus, mercuric oxide and iodide.

Sodium amalgam reduces them to secondary alcohols; phosphorus pentachloride replaces the carbonyl oxygen by chlorine, forming the ketone chlorides.

The -y-diketones are characterized by the readiness with which they yield furfurane, pyrrol and thiophene derivatives, the furfurane derivatives being formed by heating the ketones with a dehydrating agent, the thiophenes, by heating with phosphorus pentasulphide, and the pyrrols by the action of alcoholic ammonia or amines.

Like these they require water, small but indispensable quantities of salts of potassium, magnesium, sulphur and phosphorus, and supplies of carbonaceous and nitrogenous materials in different stages of complexity in the different cases.

Numerous hydrides are known; heated with red phosphorus and hydriodic acid the hydrocarbon yields mixtures of hydrides of composition C10H10 to C10H20.

Thomas, who showed that, in the presence of a slag rich in lime, the whole of the phosphorus could be removed readily.

Impurities.-The properties of iron and steel, like those of most of the metals, are profoundly influenced by the presence of small and sometimes extremely small quantities of certain impurities, of which the most important are phosphorus and sulphur, the former derived chiefly from apatite (phosphate of lime) and other minerals which accompany the iron ore itself, the latter from the pyrite found not only in most iron ores but in nearly all coal and coke.

The best tool steel should not contain more than 0.02% of either, and in careful practice it is often specified that the phosphorus and sulphur respectively shall not exceed 0.04 and o 05% in the steel for important bridges, or o 06 and 0 07% in rail steel, though some very prudent engineers allow as much as 085% or even o To% of phosphorus in rails.

The specific effect of phosphorus is to make the metal cold-short, i.e.

If the pig iron is to follow path 2, the purification which converts it into wrought iron or steel consists chiefly in oxidizing and thereby removing its carbon, phosphorus and other impurities, while it is molten, either by means of the oxygen of atmospheric air blown through it as in the Bessemer process, or by the oxygen of iron ore stirred into it as in the puddling and Bell-Krupp processes, or by both together as in the open hearth process.

In the former case there is no later chance to remove sulphur, a minute quantity of which does great harm by leading to the formation of cementite instead of graphite and ferrite, and thus making the cast-iron castings too hard to be cut to exact shape with steel tools; in the latter case the converting or purifying processes, which are essentially oxidizing ones, though they remove the other impurities, carbon, silicon, phosphorus and manganese, are not well adapted to desulphurizing, which needs rather deoxidizing conditions, so as to cause the formation of calcium sulphide, than oxidizing ones.

The processes for converting cast iron into steel can now remove phosphorus easily, but the removal of sulphur in them is so difficult that it has to be accomplished for the most part in the blast-furnace itself.

As the essential difference between cast iron on one hand and wrought iron and steel on the other is that the former contains necessarily much more carbon, usually more silicon, and often more phosphorus that are suitable or indeed permissible in the latter two, the chief work of all these conversion processes is to remove the excess of these several foreign elements by oxidizing them to carbonic oxide CO, silica S102, and phosphoric acid P 2 0 5, respectively.

Beside this their chief and easy work of oxidizing carbon, silicon and phosphorus, the conversion processes have the harder task of removing sulphur, chiefly by converting it into calcium sulphide, CaS, or manganous sulphide, MnS, which rise to the top of the molten metal and there enter the overlying slag, from which the sulphur may escape by oxidizing to the gaseous compound, sulphurous acid, S02.

As the iron oxide is stirred into the molten metal laboriously by the workman or "puddler " with his hook or "rabble," it oxidizes the silicon to silica and the phosphorus to phosphoric acid, and unites with both these products, forming with them a basic iron silicate rich in phosphorus, called " puddling " or " tap cinder."

The removal of phosphorus, a very important duty of the puddling process, requires that the cinder shall be " basic," i.e.

In the basic Bessemer process phosphorus is readily removed by oxidation, because the product of its oxidation, phosphoric acid, P 2 O 5, in the presence of an excess of base forms stable phosphates of lime and iron which pass into the slag, making it valuable as an artificial manure.

The slag, in order that it may have such an excess of base that this will retain the phosphoric acid as fast as it is formed by the oxidation of the phosphorus of the pig iron, and prevent it from being re-deoxidized and re-absorbed by the iron, should, according to von Ehrenwerth's rule which is generally followed, contain enough lime to form approximately a tetra-calcic silicate, 4CaO,S10 2 with the silica which results from the oxidation of the silicon of the pig iron and tri-calcic phosphate, 3CaO,P205, with the phosphoric acid which forms. The danger of this " rephosphorization " is greatest at the end of the blow, when the recarburizing additions are made.

The removal of the greater part of the phosphorus takes place after the carbon has been oxidized and the flame has consequently " dropped," probably because the lime, which is charged in solid lumps, is taken up by the slag so slowly that not until late in the operation does the slag become so basic as to be retentive of phosphoric acid.

Hence in making steel rich in carbon it is not possible, as in the acid Bessemer process, to end the operation as soon as the carbon in the metal has fallen to the point sought, but it is necessary to remove practically all of the carbon, then the phosphorus, and then " recarburize," i.e.

The quantity of phosphorus in the pig iron is usually known accurately, and the dephosphorization takes place so regularly that the quantity of air which it needs can be foretold closely.

Fortunately the phosphorus, turned from a curse into a blessing, develops by its oxidation the needed temperature, though the fact that this requires at least i.

In some British and Swedish " pig and ore " practice (§ 98), on the other hand, little or no scrap is used, and here the removal of the large quantity of carbon, silicon and phosphorus prolongs the process to 17 hours.

The pig and ore process is held back, first by the large quantity of carbon, and usually of silicon and phosphorus, to be removed, and second by the necessary slowness of their removal.

Thus the actual cost of conversion by the acid process is materially less than by the basic, but this difference is more than outweighed in most places by the greater cost of pig and scrap free enough from phosphorus to be used in the undephosphorizing acid process.

Such a slag not only corrodes the furnace lining, but also impedes dephosphorization, because it is irretentive of phosphorus.

It is well to remove this latter element early, so that when the carbon shall have fallen to the proportion which the steel is to contain, the steel shall already be free from phosphorus, and so ready to cast.

The lime and iron oxide melt, and, in passing up through the overlying metal, the iron oxide very rapidly oxidizes its phosphorus and thus drags it into the slag as phosphoric acid.

The ebullition from the formation of carbonic oxide puffs up the resultant phosphoric slag enough to make most of it run out of the furnace, thus both removing the phosphorus permanently from danger of being later deoxidized and returned to the steel, and partly freeing the bath of metal from the heat-insulating blanket of slag.

In the former the silicon and part of the carbon are moved rapidly, in the latter the rest of the carbon and the phosphorus are removed slowly, and the metal is brought accurately to the proper temperature and composition.

In the basic open-hearth process, on the other hand, silicon is harmful because the silica which results from its oxidation not only corrodes the lining of the furnace but interferes with the removal of the phosphorus, an essential part of the process.

By rapidly stirring molten iron oxide into molten pig iron in a furnace shaped like a saucer, slightly inclined and turning around its axis, at a temperature but little above the melting-point of the metal itself, the phosphorus and silicon are removed rapidly, without removing much of the carbon, and by this means an extremely pure cast iron is made.

In the first stage the phosphorus is removed from the molten steel by oxidizing it to phosphoric acid, P205, by means of iron oxide contained in a molten slag very rich in lime, and hence very basic and retentive of that phosphoric acid.

Floating on top of the molten metal, it rapidly oxidizes its phosphorus, and the resultant phosphoric acid combines with the lime in the overlying slag as phosphate of lime.

When the removal of the phosphorus is sufficiently complete, this slag is withdrawn from the furnace.

Next comes the deoxidizing and desulphurizing stage, of which the first step is to throw some strongly deoxidizing substance, such as coke or ferro-silicon, upon the molten metal, in order to remove thus the chief part of the oxygen which it has taken up during the oxidation of the phosphorus in the preceding stage.

If the initial quantity of phosphorus or sulphur is large, or if the removal of these impurities is to be made very thorough, the dephosphorizing or the desulphurizing slagging off may be repeated.

The reason for this is that in it the slag, by means of which all the purification must needs be done, is not heated effectively; that hence it is not readily made thoroughly liquid; that hence the removal of the phosphoric slag made in the early dephosphorizing stage of the process is liable to be incomplete; and that hence, finally, the phosphorus of any of this slag which is left in the furnace becomes deoxidized during the second or deoxidizing stage, and is thereby returned to befoul the underlying steel.

Beyond this sulphur and phosphorus can be removed in the electric furnace, whereas in the crucible process they cannot.

But cast iron for the basic open-hearth process can be made from almost any ore, because its requirements, comparative freedom from silicon and sulphur, depend on the management of the blast-furnace rather than on the composition of the ore, whereas the phosphorus-content of the cast iron depends solely on that of the ore, because nearly all the phosphorus of the ore necessarily passes into the cast iron.

Thus the basic open-hearth process, is the only one which can make steel from cast iron containing, more than o io% but less than i 80%of phosphorus.

If this carbon is all present as graphite, so that in cooling the graphite-austenite diagram has been followed strictly (§ 26), the constitution is extremely simple; clearly the mass consists first of a metallic matrix, the carbonless iron itself with whatever silicon, manganese, phosphorus and sulphur happen to be present, in short an impure ferrite, encased in which as a wholly distinct foreign body is the graphite.

Fortunately its embrittling effect on cast iron is very much less than on steel, so that the upper limit or greatest tolerable proportion of phosphorus, instead of being o.10 or better 0.08% as in the case of rail steel, may be put at 0.50% in case of machinery castings even if they are exposed to moderate shocks; at 1.60% for gas and water mains in spite of the gravity of the disasters which extreme brittleness here might cause; and even higher for castings which are not exposed to shock, and are so thin that the iron of which they are made must needs be very fluid.

The permissible phosphorus-content is lessened by the presence of either much sulphur or much manganese, and by rapid cooling, as for instance in case of thin castings, because each of these three things, by leading to the formation of the brittle cementite, in itself creates brittleness which aggravates that caused by phosphorus.

Similarly the trivalent phosphorus in the ordinary white form shows such resistance as if it were practically stable; on the other hand the red modification is in reality also stable, being formed, for instance, under the influence of light.

The Curies showed that oxygen was convertible into ozone, and Sudborough that yellow phosphorus gave the red modification when submitted to their influence.

He selected the administration of tobaccos, addressing himself especially to chemical researches under the guidance of Gay-Lussac, and gave striking proof of ability in two papers on the combinations of phosphorus with hydrogen and oxygen, published in Annales de Chimie et de Physique (1835 and 1837).

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.

The cast-iron contained nearly 3% each of silicon and graphite, and 1% each of phosphorus and manganese.

It combines readily with fluorine, chlorine and bromine, and also with sulphur, selenium, phosphorus, &c.

Parabanic acid (oxalyl urea), C0[NH C0] 21 is formed by oxidizing uric acid; or by condensing oxalic acid and urea in the presence of phosphorus oxychloride.

It decomposes violently on heating, and explodes in contact with hydrogen, sulphur, phosphorus, &c. It dissolves in water to form a deep red solution which contains permanganic acid, HMnO 4.

On the 1st of November 1772 he deposited with the Academy a sealed note which stated that sulphur and phosphorus when burnt increased in weight because they absorbed "air," while the metallic lead formed from litharge by reduction with charcoal weighed less than the original litharge because it had lost "air."

Then, perceiving that in combustion and the calcination of metals only a portion of a given volume of common air was used up, he concluded that Priestley's new air, air eminemment pur, was what was absorbed by burning phosphorus, &c., "non-vital air," azote, or nitrogen remaining behind.

In a memoir presented to the Academy in 1777, but not published till 1782, he assigned to dephlogisticated air the name oxygen, or "acidproducer," on the supposition that all acids were formed by its union with a simple, usually non-metallic, body; and having verified this notion for phosphorus, sulphur, charcoal, &c., and even extended it to the vegetable acids, he naturally asked himself what was formed by the combustion of "inflammable air" (hydrogen).

Under the head of "oxidable or acidifiable" substances, the combination of which with oxygen yielded acids, were placed sulphur, phosphorus, carbon, and the muriatic, fluoric and boracic radicles.

Phosphorus pentachloride converts them into alkyl chlorides, a similar decomposition taking place when they are heated with the haloid acids.

The ore is partly a clay ironstone, like that occurring in the Coalmeasures of England, partly an oxide of iron or haematite, and it generally contains phosphorus.

S o coo zoo goo is very earthy and of a low percentage; but it contains only a comparatively small proportion of phosphorus.

On oxidation it gives triphenylcarbinol, (C 6 H 5) 3 C OH, and reduction with hydriodic acid and red phosphorus gives benzene and toluene.

Considerable interest is attached to the remarkable series of hydrocarbons obtained by Gomberg (Ber., 1900, 33, p. 3150, et seq.) by acting on triphenylmethane chloride (from triphenylmethane carbinol and phosphorus pentachloride, or from carbon tetrachloride and benzene in the presence of aluminium chloride) and its homologues with zinc, silver or mercury.

He explained and simplified the process of obtaining phosphorus from urine, and made some admirable observations on phosphoric acid; but though he noted the increase in weight that attends the conversion of phosphorus into phosphoric acid he was content to remain an adherent of the phlogistic doctrine.

The monoxychloride, WOC14, is obtained as red acicular crystals by heating the oxide or dioxychloride in a current of the vapour of the hexachloride, or from the trioxide and phosphorus pentachloride.

Phosphorus combines directly with the metal to form W3P4; another phosphide, W2P, results on igniting a mixture of phosphorus pentoxide and tungsten.

The Hartville ores are remarkable for their high grade and purity, running from 60 to 70% metallic iron, with 22 to 5% silica, and only traces of sulphur and phosphorus.

At ordinary temperatures it unites directly with many other elements; thus with hydrogen, combination takes place in direct sunlight with explosive violence; arsenic, antimony, thin copper foil and phosphorus take fire in an atmosphere of chlorine, forming the corresponding chlorides.

Sulphur, phosphorus, carbon compounds, and the alkali metals react violently with the gas, taking fire with explosive decomposition.

He also investigated the oxygen compounds of phosphorus and nitrogen, and was ' The names of the musical instruments in those verses of the Book of Daniel have formed the basis of a controversy as to the authenticity of the book.

The sodium salt on distillation with phosphorus trisulphide gives thiophene.

The sodium salt on heating with phosphorus trisulphide yields methylthiophen.

Copper combines directly with phosphorus to form several compounds.

Wurtz's first published paper was on hypophosphorous acid (1842), and the continuation of his work on the acids of phosphorus (1845) resulted in the discovery of sulphophosphoric acid and phosphorus oxychloride, as well as of copper hydride.

While working on the olefines he noticed that a change takes place in the density of the vapour of amylene hydrochloride, hydrobromide, &c., as the temperature is increased, and in the gradual passage from a gas of approximately normal density to one of half-normal density he saw a powerful argument in favour of the view that abnormal vapour densities, such as are exhibited by sal-ammoniac or phosphorus pentachloride, are to be explained by dissociation.

Nearly all the ore is magnetite, and in the midlands it is almost wholly free of phosphorus.

Hydriodic acid and phosphorus reduce it to maleic acid and finally to succinic acid.

It combines directly with sulphur and phosphorus, and is readily oxidized when heated with metallic oxides (such as litharge, mercuric oxide, manganese dioxide, &c.).

It combines with water, forming the hydrates SbC1 5 -1-1 2 0 and SbC1 3.4H 2 O; it also combines with phosphorus oxychloride, hydrocyanic acid, and cyanogen chloride.

An antimony phosphide and arsenide are known, as is also a thiophosphate, SbPS 4, which is prepared by heating together antimony trichloride and phosphorus pentasulphide.

It is reduced by sodium amalgam to benzhydrol or diphenyl carbinol C 6 H 5 [[Choh C 6 H]] 5; a stronger reducing agent, such as hydriodic acid in the presence of amorphous phosphorus converts it into diphenylmethane (C6H5)2.

The ore is remarkably free from phosphorus, and is consequently valued for the production of pigiron to be converted into Bessemer steel.

The three monochlorpyridines are known, the a and -y compounds resulting from the action of phosphorus pentachloride on the corresponding oxypyridines, and the 1 3 compound from the action of chloroform on potassium pyrrol.

On distillation with phosphorus sulphide it gives cymene.

It combines directly with nitrogen, phosphorus, antimony and carbon, and with all the metals (except gold) to form selenides, of which those of the alkali and alkaline earth metals are soluble in water.

Pyrocatechin readily condenses to form heterocyclic compounds; cyclic esters are formed by phosphorus trichloride and oxychloride, carbonyl chloride, sulphuryl chloride, &c.; whilst ortho-phenylenediamine, o-aminophenol, and o-aminothiophenol give phenazine, phenoxazine and thiodiphenylamine.

The action of bromine is sometimes accelerated by the use of compounds which behave catalytically, the more important of these substances being iodine, iron, ferric chloride, ferric bromide, aluminium bromide and phosphorus.

The usual method employed for the preparation of the gas consists in dropping bromine on to a mixture of amorphous phosphorus and water, when a violent reaction takes place and the gas is rapidly liberated.

At the temperature of the furnace the silica (sand) attacks the calcium phosphate, forming silicate, and setting free phosphorus pentoxide, which is attacked by the carbon, forming phosphorus and carbon monoxide.

The crude phosphorus is purified by melting under water and then filtering through animal black and afterwards through chamois leather, or by treating it, when molten, with chromic acid or a mixture of potassium bichromate and sulphuric acid; this causes the impurities to rise to the surface as a scum which can be skimmed off.

It is usually sent on the market in the form of sticks, which were at one time prepared by sucking the molten material up glass tubes; but the dangers to the workmen and other disadvantages of this method have led to its replacement by a continuous process, in which the phosphorus leaves the melting-pot for a pipe surrounded by water, in which it solidifies and can be removed as a continuous rod.

Phosphorus is nearly insoluble in water, but dissolves in carbon bisulphide, sulphur chloride, benzene and oil of turpentine.

When exposed to the air a stick of phosphorus undergoes slow combustion, which is revealed by a greenish-white phosphorescence when the stick is viewed in the dark.

Several allotropic forms of phosphorus have been described, and in recent years much work has been done towards settling their identities.

The process consists in heating yellow phosphorus in iron pots provided with air-tight lids, which,.

A small quantity of the phosphorus combines with the oxygen in the vessel, and after this the operation is practically conducted in an atmosphere of nitrogen with the additional safety from any risk of explosion.

Hittorf's phosphorus is another crystalline allotrope formed by heating phosphorus with lead in a sealed tube to redness, and removing the lead by boiling the product with nitric and hydrochloric acid.

Finally a black phosphorus was described by Thenard as formed by rapidly-cooling melted phosphorus.

It decomposes when heated, hydrogen and red phosphorus being formed.

Solid Phosphoretted Hydrogen, P 4 H 2, first obtained by Le Verrier (loc. cit.), is formed by the action of phosphorus trichloride on gaseous phosphine (Besson, Comptes rendus, 111, p. 972); by the action of water on phosphorus di-iodide and by the decomposition of calcium phosphide with hot concentrated hydrochloric acid.

The tertiary phosphines are characterized by their readiness to pass into derivatives containing pentavalent phosphorus, and consequently they form addition compounds with sulphur, carbon bisulphide, chlorine, bromine, the halogen acids and the alkyl halides with great readiness.

Phosphorus oxide, P 4 0 6, discovered by Sage in 1777, is a product of the limited combustion of phosphorus in air.

It is unaffected by light when pure, but if phosphorus be present, even in minute quantity, it turns yellow and ultimately dark red.

It slowly reacts with cold water to form phosphorous acid; but with hot water it is energetically decomposed, giving much red phosphorus or the suboxide being formed with an explosive evolution of spontaneously inflammable phosphoretted hydrogen; phosphoric acid is also formed.

Sulphur trioxide and sulphuric acid oxidize phosphorus oxide, giving the pentoxide and sulphur dioxide, whilst sulphur chloride, S 2 C1 2, gives phosphoryl and thiophosphoryl chlorides, free sulphur and sulphur dioxide.

Ammonia also reacts immediately, giving phosphorus diamide, P(OH)(NH2)2, and the corresponding ammonium salt.

It is probable, however, that pure phosphorous oxide vapour is odourless, and the odour of phosphorus as ordinarily perceived is that of a mixture of the oxide with ozone.

Phosphorus tetroxide, P204, was obtained by Thorpe and Tutton by heating the product of the limited combustion of phosphorus in vacuo as a sublimate of transparent, highly lustrous, orthorhombic crystals.

Phosphoric oxide, or phosphorus pentoxide, P4010, formed when phosphorus is burned in an excess of air or oxygen, or from dry phosphorus and oxygen at atmospheric pressure (Jungfleisch, loc. cit.), was examined by Boyle and named " flowers of phosphorus " by Marggraf in 1740.

It is reduced when heated with carbon to phosphorus, carbon monoxide being formed simultaneously.

Hypophosphorous acid, HP(OH) 2, discovered by Dulong in 1816, and obtained crystalline by Thomson in 1874 (Ber., 7, P. 994), is prepared in the form of its barium salt by warming phosphorus with baryta water, removing the excess of baryta by carbon dioxide, and crystallizing the filtrate.

On heating they yield phosphine and leave a residue of pyrophosphate, or a mixture of metaand pyrophosphates, with a little phosphorus.

Phosphorous acid, P(OH) 3, discovered by Davy in 1812, may be ' obtained by dissolving its anhydride, P 4 0 61 in cold water; by immersing sticks of phosphorus in a solution of copper sulphate contained in a well-closed flask, filtering from the copper sulphide and precipitating the sulphuric acid simultaneously formed by baryta water, and concentrating the solution in vacuo; or by passing chlorine into melted phosphorus covered with water, the first formed phosphorus trichloride being decomposed by the water into phosphorous and hydrochloric acids.

The first is formed when 30% hydrogen peroxide reacts with phosphorus pentoxide or metaor pyrophosphoric acids at low temperatures and the mixture diluted with ice-cold water.

It has no action on glass in the cold, but when heated it gives phosphorus and silicon tetrafluoride.

It does not dissociate on heating as do the pentachloride and pentabromide, thus indicating the existence of pentavalent phosphorus in a gaseous compound; dissociation, however, into the trifluoride and free fluorine may be brought about by induction sparks of 150 to 200 mm.

Heated in a glass tube it gives silicon fluoride, phosphorus and sulphur, PSF 3 = PF3-f-S; 4PF 3 +3S10 2 = 3SiF 4 +P 4 +30 2.

Electric sparks give at first free sulphur and the trifluoride, the latter at a higher temperature splitting into the pentafluoride and phosphorus.

Phosphorus trichloride or phosphorous chloride, PC13, discovered by Gay-Lussac and Thenard in 1808, is obtained by passing a slow current of chlorine over heated red phosphorus or through a solution of ordinary phosphorus in carbon disulphide (purifying in the latter case by fractional distillation).

Water gives hydrochloric and phosphorous acids, with separation of red phosphorus if the water be hot.

Phosphorus pentachloride, PC15, discovered by Davy in 1810 and analysed by Dulong in 1816, is formed from chlorine and the trichloride.

The pentabromide, PBr 5, which results from phosphorus and an excess of bromine, is a yellow solid, and closely resembles the pentachloride.

Boulough (Comptes rendus, 1905, 141, p. 256), who acted with dry iodine on phosphorus dissolved in carbon disulphide; with alkalis it gives P 4 (OH).

The first is prepared by heating red phosphorus with finely powdered sulphur in a tube sealed at one end and filled with carbon dioxide.

The second, P4S7, is obtained by heating a mixture of red phosphorus and sulphur in the proportions given by P4S7+5% P4S3, and crystallizing from carbon disulphide in which P 4 S 3 is readily soluble.

Thiel (Ber., 1905, 3 8, p. 2719 1910, 43, p. 1223), who heated sulphur with phosphorus in carbon disulphide solution with a trace of iodine to 120 0 -130 0.

The atomic weight of phosphorus was determined by Berzelius, Pelouze, Jacquelin, Dumas, Schrotter, Brodie and van der Plaats.

The phosphorus used in the British pharma copoeia is obtained from calcium phosphate, and is a waxlike non-metallic substance soluble in oils and luminous in the dark.

In young animals phosphorus has a remarkable influence on the growth of bone, causing a proliferation of the jelly-like masses and finally a deposit in them of true bony material.

In some skin diseases such as psoriasis, chronic eczema and acne indurata, phosphorus is very useful, and cases of diabetes mellitus and lymphadenoma have improved under some of its compounds.

The hypophosphites have been recommended in pulmonary affections, being said to act as free phosphorus without being irritant, and the glycero-phosphates are certainly useful to stimulate metabolism.

It does not resemble phosphorus in its physiological action and cannot be used to replace it.

Poisonous amounts of phosphorus are frequently taken or administered, criminally or accidentally, it being easily accessible to the public in the form of matches or of vermin pastes.

The old French oil of turpentine is the best antidote to use in phosphorus poisoning, delaying the toxic effects; but ordinary oils are not only useless but harmful.

When some time has elapsed before treatment and the phosphorus has become absorbed, the organic degenerative changes cannot be easily controlled.

In 1762 and 1764 he published experiments in refutation of the decision of the Florentine Academy, at that time generally accepted, that water is incompressible; and in 1768 he described the preparation, by calcining oyster-shell with sulphur, of the phosphorescent material known as Canton's phosphorus.

Since conhydrine is dehydrated by phosphorus pentoxide into a mixture of a and f3 coniceines, it may be considered an oxyconine.

Le Blanc, Ber., 1888, 21, p. 2299), or by treatment with phosphorus oxychloride followed by the reduction of the resulting dichlorisoquinoline with hydriodic acid (S.

Oxygen is absorbed by stick phosphorus contained in a tubulated pipette filled with water.

Fe3P occurs as crystals in the product of fusing iron with phosphorus; it dissolves in strong hydrochloric acid.

FeP is obtained by passing phosphorus vapour over Fe2P at a red-heat.

Fe2P3 is prepared by the action of phosphorus iodide vapour on reduced iron.

Triferrin is a paranucleinate of iron, and contains 22% of iron and 21% of organically combined phosphorus, prepared from the casein of cow's milk.

Old turpentine and French oil of turpentine are antidotes to phosphorus, forming turpentine-phosphoric acid, which is inert.

The important reducing agents include hydrogen, hydrides such as those of iodine, sulphur, phosphorus, &c., carbon, many metals, potassium, sodium, aluminium, magnesium, &c., salts of lower oxyacids, lower salts of metals and lower oxides.

The alcohol is first acted upon with phosphorus and iodine, and the resulting alkyl iodide is treated with silver nitrite, which gives the corresponding nitroalkyl.

Bronze is improved in quality and strength when fluxed with phosphorus.

Alloys prepared in this way, and known as phosphor bronze, may contain only about 1% of phosphorus in the ingot, reduced to a mere trace after casting, but their value is nevertheless enhanced for purposes in which a hard strong metal is required, as for pump plungers, valves, the bushes of bearings, &c. Bronze again is improved by the presence of manganese in small quantity, and various grades of manganese bronze, in some of which there is little or no tin but a considerable percentage of zinc, are extensively used in mechanical engineering.

Many organic arsenic compounds are known, analogous to those of nitrogen and phosphorus, but apparently the primary and secondary arsines, AsH2CH3 and AsH(CH3)2, do not exist, although the corresponding chlorine derivatives, AsCl2CH3, methyl arsine chloride, and AsCl(CH3)2, dimethyl arsine chloride, are known.

C 2 H 5 SO 2 C1 (chlorides of sulphonic acids), by heating the salts of esters of sulphuric acid with potassium hydrosulphide, and by heating the alcohols with phosphorus pentasulphide.

It is not reduced by hydriodic acid and phosphorus, but sodium in the presence of amyl alcohol reduces it to tetrahydrodiphenyl C12H14.

Phosphorus is present in all cells, in considerable quantity in the nervous tissue, and in the bones as phosphates.

When taken by the mouth phosphorus is an irritant poison in large doses; in small doses the only effects noticeable consist in an increased formation of bony and connective tissue, although it is also supposed to exert a gently stimulating effect upon the nervous system.

It is also required for calcium and phosphorus absorption and utilization.

Phosphor bronze Small additions of phosphorus in tin bronze, typically 0.4% to l %, improve the castability of the alloy.

Calcium and phosphorus in milk serve to feed nanobacteria, causing calcification and cancer.

The phosphorus in solution reacts with the molybdate ion to produce a blue coloration whose intensity is directly proportional to the concentration of phosphorus.

We grow layers of crystals containing indium, phosphorus, gallium and arsenic on wafers of indium phosphide.

It's a rich source of the minerals magnesium, potassium and phosphorus.

Certain rare inherited disorders can cause normal kidneys to lose phosphorus, which causes osteomalacia.

In soils containing little phosphorus, plants with mycorrhizae have been shown to grow up to 20 times faster than those without.

Plants use the sunâs energy to fix carbon by photosynthesis and dissolved phosphorus and nitrogen to help build proteins.

The maize crop was in its second year, weeds were being stopped, and the Inga was recycling nutrients, including phosphorus.

The data in the graph at the top of the page applies to white phosphorus which contains P 4 molecules.

Only using harmless red phosphorus, the workers were soon producing six million boxes a year.

The parameter includes all forms of phosphorus ie total phosphorus.

Phosphorus can exist as poly, ortho or organic phosphorus can exist as poly, ortho or organic phosphorus.

Reactions occurred but despite many efforts only complex mixtures of hexane soluble phosphorus containing compounds could be obtained that proved impossible to identify.

Phosphate requirement The target index for soil phosphorus is Index 2 (16-25 mg/litre ).

Retardex materials can be recycled and the PP compounds containing phosphorus flame retardants retain their flame retardant properties.

Surface applications of phosphorus can stimulate rooting within the thatch layer, thereby further aggravating the thatch accumulation rate.

Phosphorus and its compounds are finding increasing application in high performance thermoplastics.

Phosphorus removal from industrial and municipal wastewater was started in the middle of the 1970s.

When heated with hydriodic acid and phosphorus, it yields n-valeric acid; and with iodine and caustic soda solution it gives iodoform, even in the cold.

It may be prepared by distilling fuming sulphuric acid, or concentrated sulphuric acid over phosphorus pentoxide, or by the direct union of sulphur dioxide with oxygen in the presence of a catalyst, such as platinized asbestos (see Sulphuric Acid).

Thus the conversion of yellow into red phosphorus evolves about one-sixth of the heat of combustion of the latter in oxygen, and so the knowledge of which variety of phosphorus has been employed is of essential importance in the thermochemistry of that element.

His terminology was vague and provoked caustic criticism from Berzelius; he assumed that all molecules contained two atoms, and consequently the atomic weights deduced from vapour density determinations of sulphur, mercury, arsenic, and phosphorus were quite different from those established by gravimetric and other methods.

Thus, hydrogen unites with but a single atom of chlorine, zinc with two, boron with three, silicon with four, phosphorus with five and tungsten with six.

But not only is the combining power or valency (atomicity) of the elements different, it is also observed that one element may combine with another in several proportions, or that its valency may vary; for example, phosphorus forms two chlorides represented by the formulae PC1 3 and PC1 51 nitrogen the series of oxides represented by the formulae N 2 0, NO, (N203), N 2 O 4, N205, molybdenum forms the chlorides MoC1 2, MoC1 3, MoC1 4, MoC1 5, MoCls(?), and tungsten the chlorides WC1 2, WCl 4, WC1 5, WC16.

For example, in phosphorus pentachloride the five units of affinity possessed by the phosphorus atom are satisfied by the five monad atoms of chlorine, but in the trichloride two are disengaged, and, it may be supposed, satisfy each other.

It is worthy of note that phosphorus and arsenic bases analogous to the amines are known (see Phosphorus and Arsenic).

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.

It is the principal inorganic constituent of bones, and hence of the "bone-ash" of commerce (see Phosphorus); it occurs with fluorides in the mineral apatite (q.v.); and the concretions known as coprolites largely consist of this salt.

It will only combine with hydrogen in the presence of a catalyst, but combines with many other elements directly; for example, phosphorus melts and then inflames, antimony burns in the vapour, and mercury when heated with iodine combines with it rapidly.

The restriction of the basic Bessemer process to pig iron containing at least i 80% of phosphorus has prevented it from getting a foothold in the United States; the restriction of the acid Bessemer process to pig iron very low in phosphorus, usually to that containing less than o ro% of that element, has almost driven it out of Germany, has of late retarded, indeed almost stopped, the growth of its use in the United States, and has even caused it to be displaced at the great Duquesne works of the Carnegie Steel Company by the omnivorous basic open-hearth.

While segregation injures the metal here, often fatally, by giving it an indeterminate excess of phosphorus and sulphur, it clearly purifies the remainder of the ingot, and on this account it ought, under certain conditions, to be promoted rather than restrained.

Phosphorus pentachloride converts it into picryl chloride, C 6 H 2 C1(NO 2) 3, which is a true acid chloride, being decomposed by water with the regeneration of picric acid and the formation of hydrochloric acid; with ammonia it yields picramide, C 6 H 2 NH 2 (NO 2) 3.

Casciorolus, a shoemaker of Bologna, who found that after ignition with combustible substances it became phosphorescent, and on this account it was frequently called Bolognian phosphorus.

Zimmermann, Ber., 1885, 18, p. 3316); by heating isoamyl nitrate with phosphorus pentoxide (E.

C. Brodie in 1853 showed that a trace of iodine also expedited the change_ The same form is also produced by submitting ordinary phosphorus to the silent electric discharge, to sunlight or the ultraviolet light.

With chlorine it gives phosphoryl and " metaphosphoryl " chlorides, the action being accompanied with a greenish flame; bromine gives phosphorus pentabromide and pentoxide which interact to give phosphoryl and " metaphosphoryl " bromides; iodine gives phosphorus di-iodide, P 2 I 4, and pentoxide, P 2 0 5; whilst hydrochloric acid gives phosphorus trichloride and phosphorous acid, which interact to form free phosphorus, phosphoric acid and hydrochloric acid.

Phosphorous oxide is very poisonous, and is responsible for the caries set up in the jaws of those employed in the phosphorus industries (see below).

Kulisch, Monats., 1894, 15, p. 276); by the action of phosphorus pentachloride on hydrocarbostyril (the inner anhydride of ortho-aminohydrocinnamic acid), the chlorinated compound first formed being then reduced by hydriodic acid (A.

It is almost insoluble in water, is miscible with absolute alcohol and ether, and dissolves sulphur, phosphorus, resins and caoutchouc. On exposure to the air it dries to a solid resin, and absorbing oxygen gives off ozone - a reaction utilized in the disinfectant called "Sanitas."

In his researches, Roscoe showed that the atomic weight of the metal as determined by Berzelius and the formulae given to the oxides were incorrect, and pointed out that the element falls into its natural place in group V of the periodic classification along with phosphorus and arsenic, and not in the chromium group where it had originally been placed.

Elements like phosphorus and silicon react with the oxygen to form acidic oxides.

We will focus on several key elements including sulfur, nitrogen, halogens, phosphorus and iron.

The meat is either turkey, chicken or lamb, and all meats are free range.Rad Cat also uses human-grade bone meal to provide the appropriate levels of calcium and phosphorus.

When naturally-occurring chemicals like nitrates and phosphorus contaminate water, the organisms don't have the right balance of nutrients to survive.

The key to proper soil fertilization is soil testing, which tells you how much, if any, nitrogen, phosphorus, potassium, and micronutrients your soils may need.

Made from ground bones, bone meal is a good source of phosphorus, which is important for root health.

Phosphate Rock adds phosphorus, calcium, and sulfur to the soil.

Phosphorus is beneficial for the early growth of plants, and it aids root growth.

Some places (including the state of Minnesota) have regulations on the use of phosphorus fertilizer, so check locally before you apply.

Phosphorus can leach out of soil and contaminate water, leading to decreased water quality and harming the creatures that live in the water.

Ringer Lawn Restore is a 10-2-6 (that's the percentage by weight of nitrogen, phosphorus and potassium, respectively) blend that is a good choice for established lawns that need a boost.

In fact, studies show that when you add large amounts of nitrogen (N), phosphorus (P) and potassium (K) that it works against you, diminishing organic material in soils.

According to the International Fertilizer Industry Association, a fertilizer contains at least 5 percent nitrogen, phosphorus, or potassium or a combination of any of the three.

Rickets-A condition caused by the dietary deficiency of vitamin D, calcium, and usually phosphorus, seen primarily in infancy and childhood, and characterized by abnormal bone formation.

Impaired kidneys cause an increased level of phosphorus in the blood, which interferes with calcium absorption.

Dietary changes may include limiting foods high in phosphorus, such as dairy products, meat, and poultry.

A phosphate binder may be recommended to keep phosphorus in the bowel (so it does not interfere with calcium absorption) where it is excreted during a bowel movement.

Too much calcium in the diet may inhibit absorption of iron, magnesium, phosphorus, and zinc.

Calcium and phosphorus are closely related minerals that should be balanced.

Phosphorus converts food to energy and supports the utilization of vitamins.

Phosphorus is closely related to calcium and the two minerals should be in balance with each other and with magnesium.

Calcium and phosphorus are stored in the bones as crystals of calcium phosphate.

Calcium and phosphorus are plentiful in foods, and dietary deficiencies are rare.

Deficiency of calcium or imbalances with phosphorus and magnesium can produce muscle cramping and digestive problems.

Phosphorus deficiency can produce anxiety.

Although diarrheal fluids deplete a number of electrolytes (sodium, potassium, chloride, calcium, phosphorus, and magnesium), the main concern in avoiding shock is replacing sodium and water.

Iron deficiency can also be caused by excess phosphorus in the diet, chronic intestinal bleeding, poor digestion and absorption, prolonged illness, ulcers, and the use of antacids.

In addition to determining serum calcium, phosphorus, and vitamin D levels, the diagnosis of calcium and phosphorus deficiency may involve taking x rays of the skeleton.

The diagnosis can be confirmed by blood tests for calcium, phosphorus, and parathyroid hormone levels and by the sheep cell test for immune function.

Vitamin D performs a major function in helping the body to maintain normal levels of both calcium and phosphorus in the bloodstream and is vital for the absorption of calcium by the bones and teeth.

This important vitamin plays a major roll in maintaining normal levels of calcium and phosphorus in the bloodstream.

Vitamin D helps bones absorb the minerals they need for growth and repair, including calcium and phosphorus.

Vitamin D is an essential nutrient responsible for your body's ability to absorb and use calcium and phosphorus.

Most of your body's phosphorus and calcium are stored in your bones and teeth.

Phosphorus is part of a major buffering system of the bloodstream.

Vitamin D helps your body absorb calcium and phosphorus.

Vitamin D, for example, is vital for calcium and phosphorus absorption.

Vitamin D helps the body regulate its levels of phosphorus, another important vitamin for bone health and growth.

Your body also needs minerals, including sodium, potassium, calcium, phosphorus, and magnesium.

By the action of phosphorus pentachloride, the hydroxyl group is replaced by chlorine.

Hydriodic acid and phosphorus at high temperature give a dihydro-compound, whilst sodium and alcohol give hexaand octo-hydro derivatives.

A thiophenol, C 6 H 5 SH, is known, and is prepared by the action of phosphorus pentasulphide on phenol, or by distilling a mixture of sodium benzene sulphonate and potassium sulphydrate.

The specifications for bull-headed rails issued by the British Engineering Standards Committee in 1904 provided for a carbon-content ranging from 0-35 to 0-50%, with a phosphorus maximum of 0.075%.

In the United States a committee of the American Society of Civil Engineers, appointed to consider the question of rail manufacture in consequence of an increase in the number of rail-failures, issued an interim report in 1907 in which it suggested a range of carbon from 0-55 to 0-65% for the heaviest sections of Bessemer steel flange rails, with a phosphorus maximum of 0.085%; while the specifications of the American Society for Testing Materials, current at the same period, put the carbon limits at o 45 to 0-55%, and the phosphorus limit at o io.

A year or two later field trials were begun in England, with the final result that basic slag has become recognized as a valuable source of phosphorus for growing crops, and is now in constant demand for application to the soil as a fertilizer.

Straight lines and semicircles were utilized for the non-metallic elements, carbon, nitrogen, phosphorus and sulphur!

Frankland had recognized the analogies existing between the chemical properties of nitrogen, phosphorus, arsenic and antimony, noting that they act as trior penta-valent.

The allotropy of arsenic and antimony is also worthy of notice, but in the case of the first element the variation is essentially non-metallic, closely resembling that of phosphorus.

Phosphorus is obtained as a soluble phosphate (which can be examined in the usual way) by lixiviating the product obtained when the substance is ignited with potassium nitrate and carbonate.

Sulphur and phosphorus can sometimes be estimated by Messinger's method, in which the oxidation is effected by potassium permanganate and caustic alkali, or by potassium bichromate and hydrochloric acid.

Mitscherlich, in the case of the acid phosphate and acid arsenate of potassium, KH 2 P(As)04, who adopted the term isomorphism, and regarded phosphorus and arsenic as isomorphously related elements.

The iron ores mined at Daiquiri near Santiago are mainly rich hematites running above 60% of iron, with very little sulphur or phosphorus admixture.

This may be effected by burning phosphorus in a confined volume of air, by the action of an alkaline solution of pyrogallol on air, by passing air over heated copper, or by the action of copper on air in the presence of ammoniacal solutions.

It does not support the combustion of a taper, but burning phosphorus and red-hot carbon will continue to burn in the gas.

It contains, however, more nickel and also phosphorus.

Phosphorus containing albumins (nucleo-albumins), caseins, vitellines, nucleo-albumins of the cellprotoplasm, mucoid nucleo-albumins.

The mucins and mucoids belong to this group; they are acid and contain no phosphorus; they give the albumin colour reactions but are not coagulated by heat.

The " phospho-glyco-proteids " resemble the mucins and mucoids in containing a carbohydrate residue, but differ in containing phosphorus.

When heated with hydriodic acid and phosphorus it forms phenylacetic acid; whilst concentrated hydrobromic acid and hydrochloric acid at moderate temperatures convert it into phenylbromand phenylchlor-acetic acids.

The amount of methyl alcohol present in wood spirit is determined by converting it into methyl iodide by acting with phosphorus iodide; and the acetone by converting it into iodoform by boiling with an alkaline solution of iodine in potassium iodide; ethyl alcohol is detected by giving acetylene on heating with concentrated sulphuric acid, methyl alcohol, !under the same circumstances, giving methyl ether.

He applied himself more particularly to the oxygen compounds, and determined with a fair degree of accuracy the ratio of carbon to oxygen in carbon dioxide, but his values for the ratio of hydrogen to oxygen in water, and of phosphorus to oxygen in phosphoric acid, are only approximate; he introduced no new methods either for the estimation or separation of the metals.

The elements which play important parts in organic compounds are carbon, hydrogen, nitrogen, chlorine, bromine, iodine, sulphur, phosphorus and oxygen.

It is also prepared by the action of phosphorus pentachloride on potassium nitrite or on nitrogen peroxide.