CARBAMIC ACID. 



IBON. 



evolved. It U soluble 111 hot or cold water, alcohol, or ethrr ; the 

 solution i quite neutral, and does not precipitate soluble salt* of 

 silver. It vapour-density U equal to 3'14. 



OarbamaK of 6/jr/ (c w H u NO,. or NHt( ^ Q } ) (*-'*o) 

 in produced from butylic. alcohol in a somewhat ximilar manner to the 

 two previously mentioned substances. Its boiling-point is about 430 

 Fahr. It crystallises in very beautiful pearly spangles, which are 

 insoluble in water, but soluble in alcohol or ether. 



Carbamatt of amyl (c it H 13 N0 4 , or NH ^H, ) * O } ) (<"' l i"'<"*< / "") 

 may also be obtained by the same method from amylic alcohol. It 

 cryatalliaM from boiling water in fine silky needles, which melt at 

 150 Fahr., and distil without alteration at 428" Fahr. 



NS., or NH i< c ^ 1 U a nearly colour- 



ftulpkocarbamic add I o,n,no 4 , or " H~ S 



lew, or slightly reddish-coloured oily body, produced by decomposing 

 tiulphocarbarnate of ammonia with dilute sulphuric or hydrochloric 

 acid. It U heavier than water, and possesses a peculiar odour some- 

 what resembling sulphuretted hydrogen. It decomposes carbonates 

 with effervescence. It is not very stable, soon decomposing into cyanic 

 acid, hydrosulphocyanic acid, and other products. 



Stlfhocarbamale of ammonia ( JIH *^H > ' I}) " obtamed b ? di " 

 getting together, in a hermetically sealed tube, at a temperature of 

 60 Fahr., a mixture of one volume of absolute alcohol saturated with 

 ammoniacal gas and a solution of 0-16 of a volume of bisulphide of 

 carbon (CS,), or sulphocarbonic acid in 0'4 of a volume of alcohol. 

 Other substances are at the some time produced. 



The sulphocarbamate of ammonia crystallises in long prisms of a 

 lemon-yellow colour, and has an odour resembling sulphide of ammo- 

 nium. Heated with caustic potash it is decomposed into sulphocyanide 

 and sulphide of potassium, water and ammonia. 



>lir tu'iiliiicarbaHuitet are produced in most cases when a soluble 

 salt of a metal U added to an alkaline sulphocarbamate. Thus : 



Sulphocarbamate of lead . . . NH ' CS ^J | 



NH,(CS), S 

 Zn S 



Nn,(CS), 8 

 Cu, S 



1 



Sulpnocarbamate of zinc 

 Subsnlphocarbamatc of copper 



The lead and zinc salts are white, the copper salt yellow. The nieke 

 salt precipitated in a similar manner is yellow-green, the mercuric salt 

 white, the platinum salt yellow-brown. Lime and baryta salts yield 

 no precipitate. 



\Vlu-n Bulphocarbamate of ammonia is dissolved in five or six parts 

 of water and aqueous solution of, chlorine gradually added, the mixture 

 being well shaken on each addition, white crystalline flocks precipitate. 

 These, purified by wanning with water, constitute l<it<lran:otliinr, the 

 decomposition by which they are produced and their composition being 

 thus expressed : 



XII,(C8),S , _ 2VH n , NH t (C8),8, 1 

 1 NU.8 ) 4 " + XH,(C8),S, f 



Thin laxly in the tiitiil/Jtiile nf iuljJi<ic<irbaiiunoninm, or simply bisul- 

 phide of ammonium, in which two equivalent* of hydrogen are replaced 

 by two equivalent* of (CS). It is almost colourless and without odour 

 when recently prejared ; slightly soluble in water, more so in alcohol 

 and etli'-i . 



\ 1 1 (CO\ S 1 

 *,</jJ>ocarbamatc of ellnjl, ' ^ j|t mfeUMr*fta**U .rntiiliij<na- 



la'ulf, is produced by the re-action of xauthic ether (disulphocarbonate 

 of ethyl) and ammonia. It is only slightly soluble in water, l.nt very 

 much so in alcohol or ether. Ily spontaneous evaporation it is obtained 

 in beautiful rlioml.oid.il prisms or octohedra, sometimes very large: 

 heated they melt at about 97 Fahr., and at a higher temperature decom- 

 pose. Xaiithogciiamidc combines with certain metallic salts, producing 

 crystalline compound*. Nitric acid converts it into a substance that 

 crystallises in primus; it has been callnl tfftifkttftMit of ethyl. 



Stlflaearbanutit of awyl, ( * H (C ft ) ' g }) .n,<ll,<,, l , 1 ,1,, w ;,(e, ii on 



oily lly, neutral to test paper, insoluble in water, soluble in alcohol 

 or ether. 



OJJ .,, 



g\V The two compound* 



Myt-carbamic arid / NH < C . H .) 



known u nl<y<lroni carbonate of mtthylaminc and milii/ilmm carbonate 

 / iil.iilnmlar are combinations of the above adds with mcthylamino 

 and ethylamine respectively. 



Etkylcarbamate of ethyl, (NH(C.H.) (CO), OJ.^ tAy i vrakal , ti - u . 



lightly oleaginous liquid, obtained by the re-action of cyanate of ethyl 

 on alcohol Boiling i-oint, 315* Fahr. ; specific gravity, <M8< ; vapour 

 density, 4-071. 



ami. t < (" * H (C,,H.) (CO^ O \\ to^^aie add, (at 



anthrauilic acid), has been obtained by Fritnche, by acting on indigo 

 with caustic potash. It crysUlliM* in colourless prisms, brilliant, 

 Urge, and transparent It unites with metals, forming crystalline 

 salt*. 



of methyl, / NH < c i H (0), j\ ./ 



I'll". ,111 oily compound, heavier than water; obtained by treating 

 sulphide of ammonium with nitrobenzoate of methyl. 



PKenyl.rarbamate of ethyl, 



is a body very 



similar to the above methyl-compound. Ammonia converts it into 

 phenyl-urea and alcohol. 



CARBAMIDE (CONH,). This substance is produced by the 

 of chlorc-carbonic acid gas on ammonia. Sal-ammoniac is also formed 

 at the same time. Under the influence of the mineral acids, carbamide 

 yields ammonia and carbonic acid, According to the recent experi- 

 ments of Natanson, carbamide is identical with urea, and the 

 formula therefore requires to be doubled (CjHJ-TjO.,). [URKA.] 

 CAKBAN1LIC ACID. [CARBAMIC ACID : / n,t!i- Ari,l.] 



CARBANILIDE, or f)ii,heiii/lcarbami<le (C M H,,>',O t ). Thi 

 stance is carbamide, in which two equivalents of hydrogen have been 

 replaced by two of the radical phenyl (C^H^). It is prepared by 

 passing chloro-carbonic acid gas into aniline. The re-action is thus 

 expressed : 



C,0,C1, + 2(C,,H,N) = 2HC1 + 



Chicle-carbonic 

 acid. 



Aniline. 



Carbanilidc. 



It is a white cn-stalline inodorous Ixxly, capable of being distilled 

 without decomposition. It fuses at 401 F. 



CARBAZOTIC ACID (C^H^NO,)^.). This acid, which has alw 

 been called picric ac'ul, iii'i-u/*" ITO/I/I* niti*- m-'ul. anil trinilrn- 



Ijlirni/lic arid, results from the action of nitric acid upon a great num- 

 ber of vegetable and animal substances. A large quantity is fur: 

 by indigo : one part of this substance reduced to coarse powder U to 

 be gently heated with eight or ten times its weight of moderately 

 strong nitric acid. The indigo dissolves with the evolution of mnoD 

 nitric oxide gas. As soon as the effervescence i ovei . the liquor is to 

 be boiled, and nitric acid added from time to time till the evolution of 

 nitric oxide ceases : on cooling, crystals of carbazotic acid are obtained, 

 which are of a brilliant yellow colour ; they are to be w;uxhud wit i 

 water, dissolved in boiling wator, and re-crystallised. Carbazotic acid 

 is however now made by acting upon carbolic acid with nitric acid. 



The pure acid is said to crystallise in equilateral triangular lamina*, 

 the primary form being an octahedron with a rhombic base. It redden., 

 litmus paper, and has a very bitter taste, and on this account it \\a> 

 long called Utter of iiuliyo. When heated, it fuses and sublime* with- 

 out decomposing. If it be rapidly heated in the air, it bnrns without 

 explosion, leaving charcoal. This acid is but slightly soluble in cold 

 water, but much more so in hot; the solution is of an intense \ 

 colour. Alcohol and ether dissolve it readily. Chlorine and iodine do 

 not act upon this acid, even when it is fused in these substances. 

 Heated with aqua regia it gives chloranile and chloropicrin. It eon- 

 tains no water, and is said to be poisonous. 



The saline compounds of this acid are called earbazotatet or nitru- 

 /,ii'riii-n. An account of them may be seen in Gerhardt's ' Traito de 

 Chimie," tome iii. p. 41. 



Carbazotic acid is now extensively employed for dyeing silk and 

 wool yellow. It is also said to be sometimes fraudulently substituted 

 for hops in the manufacture of beer. 



CARBETHYLIC ACID. [ETHYL, CarlwMc Aciil.] 



CARBIDK. [('Ainu HET.] 



CARBOBENZOIC ACID, KgntCfKe .!'<'</. An add of pro' 

 tical existence, obtained from r. It is probably impure 1 > 



add, 



CARBOHYDROQKN. [HTDROCARBOXS] 



CAKIK'I.IC ACID Ihjilr'i- rheniflic'Alcokol 



(C,,H 5 O + HO) is one of the products of coal tar, and is found amongst 

 those jxirtions which boil In'twccn the temperature of 800* and Imp . 

 It is j>rx",nvd liy w.i-hin;,' tin'- peculiar product with twice it.x weight 

 h ley. On tin- addition of an acid to thi mixte.i, . -arbolic 

 .'.id m\v lie 'obtained ill the form of a heavy oil. When pun it is a 

 heavy tnuiHiBin-nt oil, refracting light vi ly, neutral to tost 



inper, and having a specific gravity of V<1(!2 to 1 0(1.1. It h.is the taste 

 and odour of creosote, which it much resembles. They are probably 

 identical, or homologous. 



c \ICU<iMKTIIVUC ACID. [MBTHYI..J 



i Mil'.ON. Tliin element nml it- nombinotionl net an imp' 

 i-art in the liiineral constitution of our earth. Following the system 

 of Berzclius, the nulwUnces containing it nrc arranged in three groups, 

 the first eoi..iting of the mineral forms of pure carbon, the second of 

 the carbonates, and the third of those carl. oniferous masses in which 

 . omliiiiid according to the principles of organic 

 chemistiy, ami which have resulted from vegetable matter. 



The first group consults only of three essentially different varieties, 

 namely, two crystallised and one amorphous variety of carbon. The 

 crystaUiKod varieties are known under the names of DIAHO.NU and 



