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CARBO
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CARBO , the name of a See also:Roman plebeian See also:family of the gens Papiria. The following are the most important members in Roman See also:history: r. See also:GAIUS PAPIRIUS CARBO, statesman and orator. He was associated with C. See also:Gracchus in carrying out the provisions of the agrarian See also:law of Tiberius Gracchus (see GRACCHUS). When See also:tribune of the See also:people (131 B.C.) he carried a law extending voting by See also:ballot to the enactment and See also:repeal of See also:laws; another proposal, that the tribunes should be allowed to become candidates for the same See also:office in the See also:year immediately following, was defeated by the younger Scipio See also:Africanus. Carbo was suspected of having been concerned in the sudden See also:death of Scipio (129), if not his actual murderer. He subsequently went over to the optimates, and (when See also:consul in 120) successfully defended See also:Lucius Opimius, the murderer of Gaius Gracchus, when he was impeached for the See also:murder of citizens without a trial, and even went so far as to say that Gracchus had been justly slain. But the optimates did not See also:trust Carbo. He was impeached by See also:Licinius See also:Crassus on a similar See also:charge, and, feeling that he had nothing to See also:hope for from the optimates and that his condemnation was certain, he committed See also:suicide. See See also:Livy, Epit. 59; See also:Appian, See also:Bell. Civ. i. 18; See also:Veil. Pat. ii. 4; Val. Max. iii. 7. 6; A. H. J. Greenidge, History of See also:Rome (1904). 2. His son, GA1us PAPIRIUS CARBO, surnamed Arvina, was a staunch supporter of the See also:aristocracy, and was put to death by the Marian party in 82. He is known chiefly for the law (Plautia Papiria) carried by him and M. Plautius See also:Silvanus when tribunes of the people in 90 (or 89), whereby the Roman See also:franchise was offered to every See also:Italian ally domiciled in See also:Italy at the See also:time when the law was enacted, provided he made application personally within sixty days to the See also:praetor at Rome (see ROME: History, II. " The See also:Republic," See also:Period C.). The See also:object of the law was to conciliate the states at See also:war with Rome and to secure the See also:loyalty of the federate states. Like his See also:father, Carbo was an orator of distinction. See See also:Cicero, See also:Pro Archia, 4; Veil. Pat. ii. 26; Appian, Bell. Civ. i. 88. When phenol is passed through a red-hot See also:tube a complex decomposition takes See also:place, resulting in the formation of See also:benzene, See also:toluene, See also:naphthalene, &c. (J. G. Kramers, See also:Ann., 1877, 189, p. 129). See also:Chromium oxychloride reacts violently on phenol, producing hydroquinone See also:ether, O(C6H4OH)2; chromic See also:acid gives phenoquinone, and potas- sium permanganate gives paradiphenol, oxalic acid, and some salicylic acid (R. Henriques, Ber., 1888, 21, p. 1620). In alkaline See also:solution, See also:potassium permanganate oxidizes it to inactive tartaric acid and See also:carbon dioxide (0. Doebner, Ber., 1891, 24, p. 1755). When distilled over See also:lead See also:oxide, it forms diphenylene oxide, (See also:C6H4)2O : and when heated with oxalic acid and concentrated sulphuric acid, it forms aurin, C19H,403. It condenses with aceto-acetic ester, in the presence of sulphuric acid, to 13-methyl See also:coumarin (H. v. Pechmann and J. B. See also:Cohen, See also:Bee.; 1884, 17, p. 2188). The See also:hydrogen of the hydroxyl See also:group in phenol can be replaced by metals, by alkyl See also:groups and by acid radicals. The metallic derivatives (phenolates, phenates or carbolates) of the See also:alkali metals are obtained by dissolving phenol in a solution of a See also:caustic alkali, in the See also:absence of See also:air. Potassium phenolate, C6H5OK, crystallizes in See also:fine needles, is very hygroscopic and oxidizes rapidly on exposure. Other phenolates may be obtained from potassium phenolate by precipitation. The alkyl derivatives may be obtained by See also:heating phenol with one molecular proportion of a caustic alkali and of an alkyl iodide. They are compounds which greatly resemble the mixed See also:ethers of the aliphatic See also:series. They are not decomposed by boiling alkalis, but on heating with hydriodic acid they split into their components. Anisol, phenyl methyl ether, See also:C6H5.O•CH,, is prepared either by the above method or by the See also:action of diazomethane on phenol, C6HSOH+CH,N2=N2+C6H5.O•CH3 (H. v. Pechmann, Ber., 1895, 28, p. 857) ; by distilling anisic acid (paramethoxy benzoic acid) with baryta or by boiling phenyl diazonium chloride with methyl See also:alcohol. It is a colourless pleasant-smelling liquid which boils at 154.3° C. Phenetol, phenyl See also:ethyl ether, C6H5.O•C2H5, a liquid boiling at 172° C., may be obtained by similar methods. A. Hantzsch (Ber., 1901, 34, p. 3337) has shown that in the action of See also:alcohols on diazonium salts an increase in the molecular See also:weight of the alcohol and an See also:accumulation of negative groups in the aromatic See also:nucleus lead to a diminution in the yield of the ether produced and to the See also:production of a secondary reaction, resulting in the formation of a certain amount of an aromatic See also:hydrocarbon. The acid See also:esters of phenol are best obtained by the action of acid chlorides or anhydrides on phenol or its See also:sodium or potassium See also:salt, or by digesting phenol with an acid in the presence of See also:phosphorus oxychloride (F. Rasinski, Jour. f. See also:peak. Chem., 1882 [2], 26, p. 62). Phenyl acetate, C6H5.O•COCH3, a colourless liquid of boiling point 193° C., may be prepared by heating phenol with acetamide. When heated with See also:aniline it yields phenol and acetanilide. Phenyl benzoate, C6H5.0•COC6H5, prepared from phenol and benzoyl chloride, crystallizes in See also:monoclinic prisms, which melt at 68-69° C. and See also:boil at 314° C. Phenol is characterized by the readiness with which it forms substitution products; See also:chlorine and See also:bromine, for example, react readily with phenol, forming ortho- and See also:para- chlor- and -bromphenol, and, by further action, trichlor- and tribrom-phenol. lodphenol is obtained by the action of See also:iodine and iodic acid on phenol dissolved in a dilute solution of caustic potash. Nitro-phenols are readily obtained by the action of nitric acid on phenol. By the action of dilute nitric acid, ortho- and para-nitrophenols are obtained, the ortho-See also:compound being separated from the para-compound-by See also:distillation in a current of See also:steam. Ortho-nitrophenol, C6H4.0H.NO2(1.2), crystallizes in yellow needles which melt at 45° C. and boil at 214°C. Para-nitrophenol, C6H4.OH.NO2(1.4), crystallizes in See also:long colourless needles which melt at 114°C. See also:Meta-nitrophenol,C6H4.OH.NO2•(1.3), is prepared from meta-nitraniline by diazotizing the See also:base and boiling the resulting diazonium salt with See also:water. By nitrating phenol with concentrated nitric acid, no care being taken to keep the temperature of reaction down, trinitrophenol (picric acid) is obtained (see PICRIC AcID). By the reduction of nitro-phenols, the corresponding aminophenols are obtained, and of these, the meta- and para-derivatives are the most important. Para-aminophenol, C6H4.OH.See also:NH2(1.4) melts at 148° C., with decomposition. Its most important derivative is See also:phenacetin. Meta-aminophenol, C6H4.OH•NH2(1.3),and dimethyl meta-aminophenol, C6 H 4.OH. N (CH 3)2 (1.3) , are extensively employed in the manufacture of the important dyestuffs known as the rhodamines. The aminophenols also find application as developers in See also:photography, the more important of these developers being amidol, the hydrochloride of diaminophenol, ortol, the hydrochloride of Para-methylaminophenol,C6H4.0H•NHCH,•HCI(1.4), rodinal, paraaminophenol, and metol, the sulphate of a methylaminophenol sulphonic acid. Meta-aminophenol is prepared by reducing metanitrophenol, or by heating See also:resorcin with ammonium chloride and See also:ammonia to 200° C. Dimethyl-meta-aminophenol is prepared by heating meta-aminophenol with methyl alcohol and hydrochloric acid in an See also:autoclave; by sulphonation of dimethylaniline, the sulphonic acid formed being finally fused with potash; or by nitrating dimethylaniline, in the presence of sulphuric acid at 0° C. In the latter See also:case a mixture of nitro-compounds is obtained which can be separated by the addition of sodium carbonate. The meta-nitrocompound, which is precipitated last, is then reduced, and the amino group so formed is replaced by the hydroxyl group by means of the Sandmeyer reaction. Dimethyl-meta-aminophenol crystallizes in small prisms which melt at 87° C. It condenses with See also:phthalic anhydride to See also:form rhodamine, and with succinic anhydride to rhodamine S. Phenol dissolves readily in concentrated sulphuric acid, a mixture of phenol-ortho- and -para-sulphonic acids being formed. These acids may be separated by See also:conversion into their potassium salts, which are then fractionally crystallized, the potassium salt of the para-acid separating first. The ortho-acid, in the form of its aqueous solution, is sometimes used as an antiseptic, under the name ofaseptol. A thiophenol, C6H5SH, 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. It is a colourless liquid, which possesses a very disagreeable See also:smell, and boils at 168° C. Various methods have been devised for the quantitative determination of phenol. J. Messinger and G. Vortmann (Bee., 1890, e3, p. 2753) dissolve phenol in caustic alkali, make the solution u•_, to known See also:volume, take an See also:aliquot See also:part, warm it to 6o° C., and add decinormal iodine solution until the liquid is of a deep yellow See also:colour. The mixture is then cooled, acidified by means of sulphuric acid, and titrated with decinormal sodium thiosulphate solution. S. B. Schryver (Jour. of See also:Soc. Chem. See also:Industry, 1899, 18, p. 553) adds excess of sodamide to a solution of the phenol in a suitable solvent, absorbs the liberated ammonia in an excess of acid, and titrates the excess of acid. See also C. E. See also: Taken internally, in doses of from one to three grains, carbolic acid will often relieve obstinate cases of vomiting and has some value as a gastric antiseptic.
See also:Toxicology.—Carbolic acid is distinguished from all other acids so-called--except oxalic acid and hydrocyanic acid—in that it is a neurotic See also:poison, having a marked action directly upon the See also:nervous See also:system. In all cases of carbolic acid poisoning the nervous See also:influence is seen. If it be absorbed from a surgical dressing there are no irritant symptoms, but when the acid is swallowed in concentrated form, symptoms of gastro-intestinal irritation occur. The patient becomes collapsed, and the skin is See also:cold and clammy. The breathing becomes shallow, the drug killing, like nearly all neurotic poisons (alcohol, morphia, prussic acid, &c.), by See also:paralysis of the See also:respiratory centre, and the patient dying in a See also:state of See also:coma. The See also:condition of the urine is of the utmost importance, as it is often a See also:clue to the diagnosis, and in surgical cases may be the first warning that absorption is occur-See also:ring to an undue degree. The urine becomes dark See also:green in colour owing to the formation of various oxidation products such as See also:pyrocatechin. Fifteen grains constitute an exceedingly dangerous dose for an adult male of See also:average weight. Other symptoms of undue absorption are vertigo, deafness, sounds in the ears, stupefaction, a subnormal temperature, See also:nausea, vomiting and a weak See also:pulse (See also:Sir See also: The symptoms of See also:nerve-poisoning are due to the carbolic acid (or its salts) which circulate in the blood after all the sulphates in the blood have been used up in the formation of sulpho-carbolates (hence, during See also:administration of carbolic acid, the urine should frequently be tested for the presence of See also:free sulphates; as long as these occur in the urine, they are See also:present in the blood and there is no danger). The treatment is therefore to administer an See also:ounce of sodium sulphate in water by the mouth, or to inject a similar quantity of the salt in solution directly into a vein or into the subcutaneous tissues. See also:Magnesium sulphate may be given by the mouth, but is poisonous if injected intravenously. If the acid has been swallowed, See also:wash out the See also:stomach and give See also:chalk, the carbolate of See also:calcium being insoluble. Alkalis which form soluble carbolates are useless. Give ether and See also:brandy sub-cutaneously and apply hot water-bottles and blankets if there are signs of collapse. Additional information and CommentsThere are no comments yet for this article.
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