Online Encyclopedia

Search over 40,000 articles from the original, classic Encyclopedia Britannica, 11th Edition.

ANTIMONY (symbol Sb, atomic weight 12...

Online Encyclopedia
Originally appearing in Volume V02, Page 129 of the 1911 Encyclopedia Britannica.
» Make a correction to this article.
» Add information or comments to this article.
Spread the word: del.icio.us del.icio.us it!

See also:

ANTIMONY (See also:symbol Sb, atomic See also:weight 120.2) , one of the metallic chemical elements, included in the same natural See also:family of the elements as See also:nitrogen, See also:phosphorus, See also:arsenic, and See also:bismuth. Antimony, in the See also:form of its sulphide, has been known from very See also:early times, more especially in Eastern countries, reference to it being made in the Old Testament. The Arabic name for the naturally occurring See also:stibnite is " See also:kohl "; Dioscorides mentions it under the See also:term cil,u ut, See also:Pliny as stibium; and See also:Geber as antimonium. By the See also:German writers it is called Speissglanz. See also:Basil See also:Valentine alludes to it in his Triumphal See also:Car of Antimony (circa 1600), and at a later date describes the preparation of the See also:metal. Native See also:mineral antimony is occasionally found, and as such was first recognized in 1748. It usually occurs as lamellar or glanular masses, with a See also:tin-See also:white See also:colour and metallic lustre, in See also:limestone or in mineral See also:veins often in association with ores of See also:silver. Distinct crystals are rarely met with; these are See also:rhombohedral and isomorphous with arsenic and bismuth; they have a perfect cleavage parallel to the basal See also:plane, c (III), and are sometimes twinned on a rhombohedral plane, e (1io). Hardness 3-31, specific gravity 6.65-6.72. See also:Sala in See also:Sweden, Allemont in See also:Dauphine, and See also:Sarawak in See also:Borneo may be mentioned as some of the localities for this mineral. Antimony, however, occurs chiefly as the sulphide, stibnite; to a much smaller extent it occurs in See also:combination with other metallic sulphides in the minerals wolfsbergite, boulangerite, See also:bournonite, See also:pyrargyrite, &c. For the preparation of metallic antimony the crude stibnite is first Equated, to See also:free it from earthy and siliceous See also:matter, and is then roasted in See also:order to convert it into See also:oxide.

After oxidation, the product is reduced by See also:

heating with See also:carbon, care being taken to prevent any loss through volatilization, by covering the See also:mass with a layer of some protective substance such as potash, soda or See also:glauber See also:salt, which also See also:aids the refining. For See also:rich ores the method of roasting the sulphide with metallic See also:iron is sometimes employed; carbon and salt or See also:sodium sulphate being used to slag the iron. Electrolytic methods, in which a See also:solution of antimony sulphide in sodium sulphide is used as the electrolyte, have been proposed (see German Patent 67973, and also Borcher's Electro-Metallurgie), but do not yet appear to have been used on the large See also:scale. Antimony combines readily with many other metals to form See also:alloys, some of which find extensive application in the arts. Type-metal is an alloy of See also:lead with antimony and tin, to which occasionally a small quantity of See also:copper or See also:zinc is added. The presence of the antimony in this alloy gives to it hardness, and the See also:property of expanding on solidification, thus allowing a See also:sharp See also:cast of the See also:letter to be taken. An alloy of tin and antimony forms the basis of Britannia-metal, small quantities of copper, lead, zinc or bismuth being added. It is a white metal of bluish tint and is malleable and ductile. For the linings of See also:brasses, various white metals are used, these being alloys of copper, antimony and tin, and occasionally lead. Antimony is a silvery white, crystalline, brittle metal, and has a high lustre. Its specific gravity varies from 6.7 to 6.86; it melts at 432° C. (See also:Dalton), and boils between ro9o-16o0° C.

(T. Carnelley), or above 1300° (V. See also:

Meyer). Its specific See also:heat is 0.0523 (H. See also:Kopp). The vapour See also:density of antimony at 1572° C. is 10.74, and at 164o° C. 9.78 (V. Meyer, Berichte, 1889, 22, p. 725), so that the antimony See also:molecule is less complex than the molecules of the elements phosphorus and arsenic. An amorphous modification of antimony can be prepared by heating the metal in a stream of nitrogen, when it condenses in the cool See also:part of the apparatus as a See also:grey See also:powder of specific gravity 6.22, melting at 614° C. and containing 98-99% of antimony (F. Herard, Comptes Rendus, 1888, cvii. 420).

Another form of the metal, known as explosive antimony, was discovered by G. See also:

Gore (Phil. Trans., 1858, p. 185; 1859, p. 797; 1862, p. 623), on electrolysing a solution of antimony trichloride in hydrochloric See also:acid, using a See also:positive See also:pole of antimony and a negative pole of copper or See also:platinum See also:wire. , It has a specific gravity of 5.78 and always contains some unaltered antimony trichloride (from 6 to 20%, G. Gore). It is very unstable, a scratch causing it instantaneously to pass into the See also:stable form with explosive violence and the development of much heat. Similar phenomena are exhibited in the See also:electrolysis of solutions of antimony tribromide and tri iodide, the product obtained from the tribromide having a specific gravity of 5.4, and containing 18-2o % of antimony tribromide, whilst that from the tri-iodide has a specific gravity of 5.2-5.8 and contains about 22 % of hydriodic acid and antimony tri-iodide. The atomic weight of antimony has been determined by the See also:analysis of the chloride, bromide and iodide. J.

P. See also:

Cooke (Prot. Amer. Acad., 1878, xiii. r) and J. Bongartz (Berichte, 1883, 16, p. 1942) obtained the value 120, whilst F. See also:Pfeiffer (See also:Ann. Chim. et Phys. ccix. 173) obtained the value 121 from the electrolysis of the chloride. Pure antimony is quite permanent in See also:air at See also:ordinary temperatures, but when heated in air or See also:oxygen it See also:burns, forming the trioxide. It decomposes See also:steam at a red heat, and burns (especially when finely powdered) in See also:chlorine. Dilute hydrochloric acid is without See also:action on it, but on warming with the concentrated acid, antimony trichloride is formed; it dissolves in warm concentrated sulphuric acid, the sulphate Sb2(SO4)a being formed.

Nitric acid oxidizes antimony either to the trioxide Sb4O6 or the pentoxide Sb205, the product obtained depending on the temperature and concentration of the acid. It combines directly with See also:

sulphur and phosphorus, and is readily oxidized when heated with metallic oxides (such as litharge, mercuric oxide, See also:manganese dioxide, &c.). Antimony and its salts may be readily detected by the See also:orange precipitate of antimony sulphide which is produced when sulphuretted See also:hydrogen is passed through their acid solutions, and also by the See also:Marsh test (see ARSENIC); in this latter See also:case the See also:black stain produced is not soluble in See also:bleaching powder solution. Antimony compounds when heated on See also:charcoal with sodium carbonate in the reducing See also:flame give brittle beads of metallic antimony, and a white incrustation of the oxide. The antimonious compounds are decomposed on addition of See also:water, with formation of basic salts. Antimony may be estimated quantitatively by See also:conversion into the sulphide; the precipitate obtained is dried at Too° C. and heated in a current of carbon dioxide, or it may be converted into the tetroxide by nitric acid. Antimony, like phosphorus and arsenic, combines directly with hydrogen. The See also:compound formed, antimoniuretted hydrogen or stibine, SbH3, may also be prepared by the action of hydrochloric acid on an alloy of antimony and zinc, or by the action of nascent hydrogen on antimony compounds. As pre-pared by these methods it contains a relatively large amount of hydrogen, from which it can be freed by passing through a tubeimmersed in liquid air, when it condenses to a white solid. It is a poisonous colourless See also:gas, with a characteristic offensive See also:smell. In its See also:general behaviour it resembles arsine, burning with a See also:violet flame and being decomposed by heat into its constituent elements. When passed into silver nitrate solution it gives a black precipitate of silver antimonide, SbAga.

It is decomposed by the halogen elements and also by sulphuretted hydrogen. All three hydrogen atoms are replaceable by organic radicals and the resulting compounds combine with compounds of the type RC1, RBr and Rl.to form stibonium compounds. There are three known oxides of antimony, the trioxide Sb406 which is capable of combining with both acids and basesto form salts, the tetroxide Sb204 and the pentoxide Sb205. Antimony trioxide occurs as the minerals yalentinite and senarmontite, and can be artificially prepared by burning antimony in air; by heating the metal in steam to a See also:

bright red heat; by oxidizing melted antimony with litharge ; by decomposing antimony trichloride with an aqueous solution of sodium carbonate, or by the action of dilute nitric acid on the metal. It is a white powder, almost insoluble in water, and when volatilized, condenses in two crystalline forms, either octahedral or prismatic. It is insoluble in sulphuric and nitric acids, but is readily soluble in hydrochloric and tartaric acids and in solutions of the See also:caustic alkalies. On strongly heating in air it is converted into the tetroxide. The corresponding hydroxide, orthoantimonious acid, Sb(OH) a, can be obtained in a somewhat impure form by precipitating See also:tartar emetic with dilute sulphuric acid; or better by decomposing antimonyl tartaric acid with sulphuric acid and drying the precipitated white powder at loo° C. Antimony tetroxide is formed by strongly heating either the trioxide or pentoxide. It is a non-volatile white powder, and has a specific gravity of 6.6952; it is insoluble in water and almost so in acids—concentrated hydrochloric acid dissolving a small quantity. It is decomposed by a hot solution of See also:potassium bitartrate. Antimony pentoxide is obtained by repeatedly evaporating antimony with nitric acid and heating the resulting antimanic acid to a temperature not above 275° C.; by heating antimony with red mercuric oxide until the mass becomes yellow (J.

See also:

Berzelius) ; or by evaporating antimony trichloride to dryness with nitric acid. It is a See also:pale yellow powder (of specific gravity 6.5), which on being heated strongly gives up oxygen and forms the tetroxide. It is insoluble in water, but dissolves slowly in hydrochloric acid. It possesses a feeble acid See also:character, giving metantimoniates when heated with alkaline See also:carbonates. Orthoantimonic acid, H3SbO4, is obtained by the decomposition of its potassium salt with nitric acid (A. Geuther) ; or by the addition of water to the pentachloride, the precipitate formed being dried over sulphuric acid (P. See also:Conrad, Chem. See also:News, 1879, xl. 198). It is a white powder almost insoluble in water and nitric acid, and when heated, is first converted into metantimonic acid, HSbO3, and then into the pentoxide Sb205. Pyroantimonic acid, H4Sb207 (the metantimonic acid of E. See also:Fremy), is obtained by decomposing antimony pentachloride with hot water; and drying the precipitate so obtained at too° C.

It is a white powder which is more soluble in water and acids than orthoantimonic acid. It forms two See also:

series of salts; of the types M2H2Sb2O7 and M4Sb2O7. Metantimonic acid, HSbO3, can be obtained by heating orthoantimonic acid- to 175° C., or by See also:long See also:fusion of antimony with antimony sulphide and See also:nitre. The fused mass is extracted with water, nitric acid is added to the solution, and the precipitate obtained washed with water (J. Berzelius). It is a white powder almost insoluble in water. On See also:standing with water for some See also:time it is slowly converted into the ortho-acid. Compounds of antimony with all the halogen elements are known, one See also:atom of the metal combining with three or five atoms of the halogen, except in the case of See also:bromine, where only the tribromide is known. The See also:majority of these halide compounds are decomposed by water, with the formation of basic salts. Antimony trichloride (" See also:Butter of Antimony "), SbCl3, is obtained by burning the metal in chlorine; by distilling antimony with excess of mercuric chloride; and by fractional See also:distillation of antimony tetroxide or trisulphide in hydrochloric acid solution. It is a colourless deliquescent solid of specific gravity 3.06; it melts at 73.2°C. (H.

Kopp) to a colourless oil; and boils at 223° (H. Capitaine). It is soluble in See also:

alcohol and in carbon bisulphide, and also in a small quantity of water; but with an excess of water it gives a precipitate of various oxychlorides, known as powder of See also:algaroth (q.v.). These precipitated oxychlorides on continued boiling with water lose all their chlorine and ultimately give a See also:residue of antimony trioxide. It combines with chlorides of the See also:alkali metals to form See also:double salts, and also with See also:barium, See also:calcium, See also:strontium, and See also:magnesium chlorides. Antimony pentachloride, SbC15, is prepared by heating the trichloride in a current of chlorine. It is a nearly colourless fuming liquid of unpleasant smell, which can be solidified to a mass of crystals melting at -6° C. It dissociates into the trichloride and chlorine when heated. It combines with water, forming the hydrates SbC15•H20 and SbCl5.4H20; it also combines with phosphorus oxychloride, hydrocyanic acid, and See also:cyanogen chloride. In See also:chloroform solution it combines with anhydrous oxalic acid to form a compound, Sb2CI8(C204), which is to be considered as COOSbCI4 tetra-chlorstibonium oxalate (R. Anschiitz and See also:Evans, OOSbC14 Annalen, 1887, ccxxxix. 235).

Antimony( chloride, SbOC1, is produced by the decomposition of one part of the trichloride with four parts of water. Prepared in this way it contains a small quantity of the unaltered chloride, which can be removed by See also:

ether or carbon bisulphide. It is a white powder insoluble in water, alcohol and ether. On heating, it is converted into the oxychloride Sb4OsC12 (Sb203.SbOCI). Antimony oxychloride, SbOCI3, is formed by addition of the calculated quantity of water to See also:ice-cooled antimony pentachloride, SbC15+See also:H2O=SbOCI3+2HCI. It forms a yellowish crystalline precipitate which in moist air goes to a thick liquid. Compounds of See also:composition, SbOCI3•2SbC16 and SbO,C1.2SbOCIa, have also been described (W. C. See also:Williams, Chem. News. 1871, See also:xxiv. 234) Antimony tribromide.

SbBra, and tti-iodide, Sbla, may be prepared by the action of antimony on solutions of bromine or See also:

iodine in carbon bisulphide. The tribromide is a coiourless crystalline mass of specific gravity 4.148 (23°), melting at 90° to 94° C. and boiling at 2754° C. (H. Kopp). The tri-iodide forms red-coloured crystals of specific gravity 4.848 (26°), melting at 165° to 167° C. and boiling at 4o1° C. By the action of water they give oxybromides and oxyiodides SbOBr, Sb4O5Br2, SbOI. Antimony penta-iodide, SbI5, is formed by heating antimony with excess of iodine, in a sealed See also:tube, to a temperature not above 13o° C. I t forms a dark See also:brown crystalline mass, melting at 78° to 79° C., and is easily dissociated on heating. Antimony triflhoride, SbF3, is obtained by dissolving the trioxide in aqueous hydrofluoric acid or by distilling antimony with mercuric fluoride. By rapid evaporation of its solution it may be obtained in small prisms. The pentafluoride SbF5 results when metantimonic acid is dissolved in hydrofluoric acid, and the solution is evaporated. It forms an amorphous gummy mass, which is decomposed by heat.

Oxyfluorides of composition SbOF and SbOF3 are known. Two sulphides of antimony are definitely known, the trisulphide Sb2S2 and the pentasulphide Sb,Ss; a third, the tetrasulphide Sb2S4, has also been described, but its existence is doubtful. Antimony trisuiphide, SbzS,, occurs as the mineral antimonite or stibnite, from which the commercial product is obtained by a See also:

process of liquation. The amorphous variety may be obtained from the crystalline form by dissolving it in caustic potash or soda or in solutions of alkaline sulphides, and precipitating the hot solution by dilute sulphuric acid. The precipitate is then washed with water and dried at loo° C., by which treatment it is obtained in the anhydrous, form. On precipitating antimony trichloride or tartar emetic in acid solution with sulphuretted hydrogen, an orange-red precipitate of the hydrated sulphide is obtained, which turns black on being heated to 20o° C The trisuiphide heated in a current of hydrogen is reduced to the metallic See also:state: it burns in air forming the tetroxide, and is soluble in concentrated hydrochloric acid, in solutions of the caustic alkalis, and in alkaline sulphides. By the See also:union of antimony trisulphide with basic sulphides, livers of antimony are obtained. These substances are usually prepared by fusing their components together, and are dark powders which are less soluble in water the more antimony they contain. These thioantimonites are used in the vulcanizing of See also:rubber and in the preparation of matches. Antimony pentasulphide, SbzSs, is prepared by precipitating a solution of the pentachloride with sulphuretted hydrogen, by decomposing " Schlippe's salt " (q.v.) with an acid, or by passing sulphuretted hydrogen into water containing antimonic acid. It forms a See also:fine dark orange powder, insoluble in water, but readily soluble in aqueous solutions of the caustic alkalis and alkaline carbonates. On heating in See also:absence of air, it decomposes into the trisulphide and sulphur.

An antimony phosphide and arsenide are known, as is also a thiophosphate, SbPS4, which is prepared by heating together antimony trichloride and phosphorus pentasulphide. Many organic compounds containing antimony are known. By distilling an alloy of antimony and sodium with mythyl iodide, mixed with See also:

sand, trimethyl stibine, Sb(See also:CH3)a, is obtained; this combines with excess of methyl iodide to form tetramethyl stibonium iodide, Sb(CH,)4I. From this iodide the trimethyl stibine may be obtained by distillation with an alloy of potassium and antimony in a current of carbon dioxide. It is a colourless liquid, slightly soluble in water, and is spontaneously inflammable. The stibonium iodide on treatment with moist silver oxide gives the corresponding tetramethyl stibonium hydroxide, Sb(CHa)4OH, which forms deliquescent crystals, of alkaline reaction, and absorbs carbon dioxide readily. On distilling trimethyl stibine with zinc methyl, antimony tetra-methyl and penta-methyl are formed. Corresponding antimony compounds containing the See also:ethyl See also:group are known, as is also a tri-phenyl stibine, Sb(C6Hs)a, which is prepared from antimony trichloride, sodium and monochlorbenzene. See Chung Yu Wang, Antimony (1909). Antimony in See also:Medicine.—So far back as Basil Valentine and See also:Paracelsus, antimonial preparations were in See also:great See also:vogue as medicinal agents, and came to be so much abused that a See also:pro- II. 5hibition was placed upon their employment by the Pais See also:parlement in 1566. Metallic antimony was utilized to make goblets in which See also:wine was allowed to stand so as to acquire emetic properties, and " See also:everlasting" pills of the metal, supposed to See also:act by contact merely, were administered and recovered for future use after they had fulfilled their purpose.

Antimony compounds act as irritants both externally and internally. Tartar emetic (antimony tartrate) when swallowed, acts directly on the See also:

wall of the See also:stomach, producing vomiting, and after absorption continues this effect by its action on the medulla. It is a powerful cardiac depressant, diminishing both the force and frequency of the See also:heart's See also:beat. It depresses respiration, and in large doses lowers temperature. It depresses the See also:nervous See also:system, especially the See also:spinal See also:cord. I.t is excreted by all the secretions and excretions of the See also:body. Thus as it passes out by the bronchial mucous membrane it increases the amount of secretion and so acts as an expectorant. On the skin its action is that of a diaphoretic, and being also excreted by the bile it acts slightly as a cholagogue. Summed up, its action is that of an irritant, and a cardiac and nervous depressant. But on See also:account of this depressant action it is to be avoided for See also:women and See also:children and rarely used for men. See also:Toxicology.—Antimony is one of the " protoplasmic " poisons, directly lethal to all living matter. In acute poisoning by it the symptoms are almost identical with those of arsenical poisoning, which is much commoner (See ARsnauc).

The See also:

post-mortem appearances are also very similar, but the gastro-intestinal irritation is much less marked and inflammation of the lungs is more commonly seen. If the patient is not already vomiting freely the treatment is to use the stomach-See also:pump, or give sulphate of zinc (gr. 10-30) by the mouth or apomorphine (gr. a---Ay) subcutaneously. Frequent doses of a teaspoonful of See also:tannin dissolved in water should be administered, together with strong See also:tea and See also:coffee and mucilaginous fluids. Stimulants may be given subcutaneously, and the patient should be placed in See also:bed between warm blankets with hot-water bottles. Chronic poisoning by antimony is very rare, but resembles in essentials chronic poisoning by arsenic. In its medico-legal aspects antimonial poisoning is of little and lessening importance.

End of Article: ANTIMONY (symbol Sb, atomic weight 120.2)

Additional information and Comments

There are no comments yet for this article.
» Add information or comments to this article.
Please link directly to this article:
Highlight the code below, right click, and select "copy." Then paste it into your website, email, or other HTML.
Site content, images, and layout Copyright © 2006 - Net Industries, worldwide.
Do not copy, download, transfer, or otherwise replicate the site content in whole or in part.

Links to articles and home page are always encouraged.

[back]
ANTIMACHUS 		[next]
ANTINOMIANS (Gr. avri, against, v6 tos, law)

Site © 2006 - Net Industries