FLUORENE (a-diphenylene methane), C 13 H 10 or (C6H4)2CH2, a hydrocarbon found in coal-tar.
The relation between the heat of combustion of a hydrocarbon and its heat of formation may be readily seen from the following example.
It thus possesses the same composition as the hydrocarbon of gutta-percha and as that of oil of turpentine and other terpenes which are the chief components of essential oils.
BENZENE, C 6 H 6, a hydrocarbon discovered in 1825 by Faraday in the liquid produced in the compression of the illuminating gas obtained by distilling certain oils and fats.
ANTHRACENE (from the Greek civOpa, coal), C 14 H 10, a hydrocarbon obtained from the fraction of the coal-tar distillate boiling between 270° and 400° C. This high boiling fraction is allowed to stand for some days, when it partially solidifies.
Paschen proved that the emission spectra of water vapour as observed in an oxyhydrogen flame, and of carbon dioxide as observed in a hydrocarbon flame may be obtained by heating aqueous vapour and carbon dioxide respectively to a few hundred degrees above the freezing point.
The hydrocarbon of gutta-percha yields similar results and is therefore closely related to caoutchouc.
PICENE, a hydrocarbon found in the pitchy residue obtained in the distillation of peat-tar and of petroleum.
HYDROCARBON, in chemistry, a compound of carbon and hydrogen.
Starting with a solid hydrocarbon of definite composition, it would be theoretically possible to decompose it entirely into carbon, hydrogen, ethylene and methane, and, by rapidly removing these from the heating zone before any secondary actions took place, to prevent formation of tar.
Deferring the detailed discussion of cyclic or ringed hydrocarbons, a correlation of the various types or classes of compounds which may be derived from hydrocarbon nuclei will now be given.
It will be seen that each type depends upon a specific radical or atom, and the copulation of this character with any hydrocarbon radical (open or cyclic) gives origin to a compound of the same class.
The readiness with which ethylene is acted on in comparison with other types of hydrocarbon, for example, is in harmony, he considers, with the circumstance that the greatest distortion must be involved in its formation, as if deflected into parallelism each valency will be drawn out of its position through 2.109° 28'.
Everybody agrees that carbon is necessary for its appearance, but some believe it to be due to a hydrocarbon, others to carbon monoxide, and others to volatilized carbon.
Pararosaniline was reduced to the corresponding leuco compound (paraleucaniline), from which by diazotization and boiling with alcohol, the parent hydrocarbon was obtained (H 2 N C 5 H 4) 2 C:C 6 H 4 :NH 2 Cl - HC(C6H4NH2 HCl)3 - >HC(C6H4N2C13) Pararosaniline hydrochloride.
A large number of arrangements for carrying out the cracking process have been proposed and patented, probably the earliest directly bearing on the subject being that of James Young, who in 1865 patented his " Improvements in treating hydrocarbon oils."
Lavoisier, to whom chemistry was primarily the chemistry of oxygen compounds, having developed the radical theory initiated by Guyton de Morveau, formulated the hypothesis that vegetable and animal substances were oxides of radicals composed of carbon and hydrogen; moreover, since simple radicals (the elements) can form more than one oxide, he attributed the same character to his hydrocarbon radicals: he considered, for instance, sugar to be a neutral oxide and oxalic acid a higher oxide of a certain radical, for, when oxidized by nitric acid, sugar yields oxalic acid.
It is necessary clearly to distinguish such compounds as the amino- (or amido-) acids and acid-amides; in the first case the amino group is substituted in the hydrocarbon residue, in the second it is substituted in the carboxyl group.
Other hydrocarbon nuclei generally classed as aromatic in character result from the union of two or more benzene nuclei joined by one or two valencies with polymethylene or oxidized polymethylene rings; instances of such nuclei are indene, hydrindene, fluorene, and fluoranthene.
Substitution of the Benzene Ring.-As a general rule, homologues and mono-derivatives of benzene react more readily with substituting agents than the parent hydrocarbon; for example, phenol is converted into tribromphenol by the action of bromine water, and into the nitrophenols by dilute nitric acid; similar activity characterizes aniline.
It was found that the results were capable of expression by the empirical relation CaH2b= 104.3b+49'09m+105.47n, where C a H 2b denotes the formula of the hydrocarbon, m the number of single carbon linkings and n the number of double linkings, m and n being calculated on the Kekule formulae.
It follows therefore that two hydrocarbon radicals are bound to the carbon monoxide residue with the same strength as they combine to form a paraffin.
It was based on an accidental observation of the action of metallic aluminium on amyl chloride, and consists in bringing together a hydrocarbon and an organic chloride in presence of aluminium chloride, when the residues of the two compounds unite to form a more complex body.
STYROLENE, C 6 H 5 CH:CH 2, also known as phenylethylene or vinylbenzene, an aromatic hydrocarbon found to the extent of 1 to 4% in storax; it also occurs with crude xylene in coal tar fractions.
It is convenient to distinguish between aliphatic and aromatic acids; the first named being derived from open-chain hydrocarbons, the second from ringed hydrocarbon nuclei.
RETENE (methyl isopropyl phenanthrene), CisHis, a hydrocarbon present in the coal-tar fraction, boiling above 360° C.; it also occurs in the tars obtained by the distillation of resinous woods.
The graphite veins in the older crystalline rocks are probably akin to metalliferous veins and the material derived from deep-seated sources; the decomposition of metallic carbides by water and the reduction of hydrocarbon vapours have been suggested as possible modes of origin.
In this method of preparation it is found that the secondary alcohols decompose more readily that the primary alcohols of the series, and when sulphuric acid is used, two phases are present in the reaction, the first being the building up of an intermediate sulphuric acid ester, which then decomposes into sulphuric acid and hydrocarbon: C2H 5 OH->C 2 H 5 HSO 4 ->C 2 H 4 +-H 2 SO 4.
33 28, 3329 (1901)] prepare sodium cyanamide by melting sodium with carbons or some hydrocarbon, and passing ammonia over the melt at from 400 0 -600° C. The temperature is then raised to 700°-800° C., and the sodium cyanamide in contact with the residual carbon forms sodium cyanide.
Two monosulphonic acids (a and 0) result by acting with sulphuric acid on the hydrocarbon, the a-acid predominating at low temperatures (80° C. and under) and the 0-acid at higher temperatures (170°-200° C.).
DIAZO COMPOUNDS, in organic chemistry, compounds of the type R N 2 X (where R = a hydrocarbon radical, and X = an acid radical or a hydroxyl group).
Jochem (Ber., 1901, 34, p. 3337), who arrived at the conclusion that the normal decomposition of diazonium salts by alcohols results in the formation of phenolic ethers, but that an increase in the molecular weight of the alcohol, or the accumulation of negative groups in the aromatic nucleus, diminishes the yield of the ether and increases the amount of the hydrocarbon formed.
They may be regarded as the anhydrides of the alcohols, being formed by elimination of one molecule of water from two molecules of the alcohols; those in which the two hydrocarbon radicals are similar are known as simple ethers, and those in which they are dissimilar as mixed ethers.
TRIPHENYLMETHANE, (C 6 H 5) 3 CH, a hydrocarbon, important as being the parent substance of several series of exceedingly valuable dyestuffs, e.g.
The last reaction is most important, for it established the connexion between this hydrocarbon and the rosanilines.
It is readily soluble in hydrocarbon solvents, in chloroform and in alcohol.
Dewar and Jones suggest that in the latter reaction it is the metallic nickel which is probably the reducing agent effecting the change, since it is only dissolved in any quantity when the anthracene hydrocarbon is produced.
When mesitylene is used, the reaction does not proceed beyond the aldehyde stage since hydrocarbon formation is prevented by the presence of a methyl group in the ortho-position to the -CHO group. Acids and alkalis are in general without action on nickel carbonyl.
ELATERITE, also termed Elastic Bitumen and Mineral Caoutchouc, a mineral hydrocarbon, which occurs at Castleton in Derbyshire, in the lead mines of Odin and elsewhere.
But its chief technical application depends upon the formation of sulphonic acids when it reacts with aromatic hydrocarbon residues; these compounds being important either as a step towards the preparation of hydroxy-compounds, e.g.
Von Hofmann continued the investigation, and established their recognition as ammonia in which one or more hydrogen atoms had been replaced by hydrocarbon radicals, thus formulating the " ammonia type."
Considering derivatives primarily concerned with transformations of the hydroxyl group, we may regard our typical acid as a fusion of a radical R CO - (named acetyl, propionyl, butyl, &c., generally according to the name of the hydrocarbon containing the same number of carbon atoms) and a hydroxyl group. By replacing the hydroxyl group by a halogen, acid-haloids result; by the elimination of the elements of water between two molecules, acid-anhydrides, which may be oxidized to acid-peroxides; by replacing the hydroxyl group by the group. SH, thio-acids; by replacing it by the amino group, acid-amides (q.v.); by replacing it by the group - NH NH2, acid-hydrazides.
The properties of caoutchouc clearly show, however, that its actual molecular structure is considerably more complex than is represented by the empirical formula, and that it is to be regarded as the polymer of a terpene or similar hydrocarbon and composed of a cluster of at least ten or twenty molecules of the formula C5H8.
PHENANTHRENE, C14H10, a hydrocarbon isomeric with anthracene, with which it occurs in the fraction of the coal tar distillate boiling between 270°-400° C. It may be separated from the anthracene oil by repeated fractional distillation, followed by fractional crystallization from alcohol (anthracene being the less soluble), and finally purified by oxidizing any residual anthracene with potassium bichromate and sulphuric acid (R.
C (OH): C 6 H 4; and with hydriodic acid at i so C. or on distillation with zinc dust, the hydrocarbon anthracene, C 14 H 10.
There seem to be characteristic bands, however, of any one series of radicals between woo and about i roo, which would indicate what may be called the central hydrocarbon group, to which other radicals may be bonded.
Hantzsch, Ber., This assumption also shows the relationship of the diazonium hydroxides to other quaternary ammonium compounds, for most of the quaternary ammonium hydroxides (except such as have the nitrogen atom attached to four saturated hydrocarbon radicals) are unstable, and readily pass over into compounds in which the hydroxyl group is no longer attached to the amine nitrogen; thus the syn-diazo hydroxides are to be regarded as pseudo-diazonium derivatives.
65, well, 7riwv, fat), a hydrocarbon of the paraffin series, probably a pentane, C 5 H 12, discovered by K.
FLUORANTHENE, C15H10, also known as idryl, a hydrocarbon occurring with phenanthrene, pyrene, diphenyl, and other substances in "Stupp" fat (the fat obtained in working up the mercury ores in Idria), and also in the higher boiling fractions of the coal tar distillate.
Nutmeg butter yields on distillation with water a volatile oil to the extent of about 6%, consisting almost entirely of a hydrocarbon called myristicene, CioHis, boiling at 165° C. It is accompanied by a small quantity of an oxygenated oil, myristicol, isomeric with carvol, but differing from it in not forming a crystalline compound with hydrosulphuric acid.
Cyclo-pentane, C5H10, is obtained from cyclo-pentanone by reducing it to the corresponding secondary alcohol, converting this into the iodo-compound, which is finally reduced to the hydrocarbon (J.
Cyclo-octane, C 8 H, 6 is obtained by the reduction of the above unsaturated hydrocarbon by the Sabatier and Senderens's method.
The solubility of naphthalene by various oils has led some engineers to put in naphthalene washers, in which gas is brought into contact with a heavy tar oil or certain fractions distilled from it, the latter being previously mixed with some volatile hydrocarbon to replace in the gas those illuminating vapours which the oil dissolves out; and by fractional distillation of the washing oil the naphthalene and volatile hydrocarbons are afterwards recovered.
PYRENE, C16H10, a hydrocarbon found together with chrysene in the last portion of the coal tar distillate, and also in "Stupp" fat.
Consider now the combustion of a hydrocarbon of the general formula CH 2m.
When this volatile liquid hydrocarbon (isoprene) is allowed ro stand for some time in a closed bottle, it gradually passes into a substance having the principal properties of natural caoutchouc. The same change of isoprene into caoutchouc may also be effected by the action of certain chemical agents.
Numerous hydrides are known; heated with red phosphorus and hydriodic acid the hydrocarbon yields mixtures of hydrides of composition C10H10 to C10H20.