VIII. On the movements of the flame in the explosion of gases.

1903 ◽  
Vol 200 (321-330) ◽  
pp. 315-352 ◽  
Author(s):  
Harold Baily Dixon ◽  
E. H. Strange ◽  
E. Graham ◽  
R. Hughes Jones ◽  
J. Bower ◽  
...  
Keyword(s):  
High Temperatures ◽  
Carbonic Acid ◽  
Gaseous Mixture ◽  
Glass Tube ◽  
Chemical Action ◽  
Specific Heats ◽  
Careful Measurement ◽  
Humphry Davy ◽  
Rate Of Movement

(1.) On the Rate of Movement of the Flam, and the produced in theExplosion of Gases. Humphry Davy was the first to observe the rate at which an explosion of gases was propagated in a tube, and he also made the first rough experiment on the tem­perature reached in an explosion. When gas from the distillation of coal (which he found more inflammable than fire-damp) was mixed with eight times its volume ofair, and was fired in a glass tube 1 foot long and 1/4 inch in diameter, the flame took more than a second to traverse the tube. When cyanogen mixed with twice its volume of oxygen was fired in a bent tube over water, the quantity of water displaced showed that the gases had expanded fifteen times their original bulk. Bunsen, in 1867, made the first careful measurement of the rate at which an explosion is propagated in gases, and he also made the first systematic researches on the pressure and temperature produced by the explosion of gases in closed vessels. His results led him to the remarkable conclusion that there was a discontinuous combustion in explosions. When electrolytic gas, or when carbonic oxide with haltits volume of oxygen, is fired, only one-third of the mixture is burnt, according to Bunsen, raising the temperature of the whole to about 3000° C. No further chemical action then occurs until the gaseous mixture falls, by cooling, below 2500° C. Then a further combustion begins, and so on<italic>per Saltum</italic>. These deductions were criticised by Berthelot, who pointed out that they assumed the constancy of the specific heats of steam and of carbonic acid at high temperatures.

scholarly journals On the movements of the flame in the explosion of gases

1902 ◽  
Vol 70 (459-466) ◽  
pp. 471-483
Keyword(s):  
Gaseous Mixture ◽  
Chemical Action ◽  
Careful Measurement

Bunsen, in 1867, made the first careful measurement of the rate at which an explosion is propagated in gases, and he also made the first systematic researches on the pressure and temperature produced by the explosion of gases in closed vessels. His results led him to the remarkable conclusion that there was a discontinuous combustion in explosions. When electrolytic gas, or when carbonic oxide with half its volume of oxygen is fired, only one-third of the mixture is burnt, according to Bunsen, raising the temperature of the whole to about 3000ºC. No further chemical action then occurs until the gaseous mixture falls by cooling below 2500º.

scholarly journals Bakerian Lecture—On certain phenomena of voltaic ignition, and on the decomposition of water into its constituent gases by heat

1851 ◽  
Vol 5 ◽  
pp. 657-659
Keyword(s):  
Carbonic Acid ◽  
Glass Tube ◽  
Platinum Wire ◽  
Philosophical Magazine ◽  
Decomposition Of Water

The author refers to an eudiometer, an account of which was published by him in the ‘Philosophical Magazine’ for 1840, formed of a glass tube, into the closed extremity of which a loop of plati­num wire was sealed. The gases to be analysed were mixed in this tube with a given volume of oxygen and hydrogen, and detonated or slowly combined by the voltaic ignition of the platinum wire. He was thence led to try a further set of experiments on the analysis, by this instrument, of such gases and vapours as are decomposable by heat; the process being capable of much greater exactness than the received one of passing them through ignited tubes. The re­sults of the analyses of several gases by this means are given in the paper. When carbonic acid and hydrogen are mixed in equal volumes and exposed to the ignited wire, the hydrogen abstracts oxygen from the carbonic acid, and leaves carbonic oxide. Con­versely, when carbonic oxide is exposed over water to the ignited wire, it abstracts oxygen from the aqueous vapour, and forms car­bonic acid. It thus appeared, that provided there were bodies present capable of absorbing by affinity the elements of water, ignited platinum would either compose or decompose water. The author was thence led to hope that he might by ignited platinum decompose water into its constituents, without absorption by other bodies, and thus pro­duce converse effects to those already known. In this he ultimately succeeded by various methods, in some of which the ignition was produced by electrical means; in others by ordinary calorific pro­cesses, such as the oxyhydrogen blowpipe, &c.

scholarly journals II. On the properties of matter in the gaseous and liquid states under various conditions of temperature and pressure

1887 ◽  
Vol 178 ◽  
pp. 45-56 ◽  
Keyword(s):  
Carbonic Acid ◽  
Gaseous Mixture ◽  
Acid Gas ◽  
Whole Space ◽  
Intimate Mixture ◽  
Oxygen Gas ◽  
The Moment ◽  
Liquid States ◽  
Elastic Fluids ◽  
Mixed Gases

According to Dalton, the particles of one gas possess no repulsive or attractive power with regard to the particles of another gas; and accordingly, if m measures of a gas A be mixed with n measures of another gas B, each will occupy m + n measures of space. The density of A in such a mixture will be m / m + n' and of B, n / m + n' , the pressure upon any one particle of such a gaseous mixture arising solely from particles of its own kind. “It is scarcely necessary,” Dalton remarks, “to insist upon the application of this hypothesis to the solution of all our difficulties respecting the constitution of mixed gases where no chemical union ensues. The moment we admit it every difficulty vanishes. The atmosphere, or, to speak more properly, the compound of atmospheres, may exist together in the most intimate mixture without any regard to their specific gravities, and without any pressure upon one another. Oxygen gas, azotic gas, hydrogenous gas, carbonic acid gas, aqueous vapour, and probably several other elastic fluids, may exist in company under any pressure, and at any temperature, without any regard to their specific gravities, and without any pressure upon one another, while each of them, however paradoxical it may appear, occupies the whole space allotted to them all.” In conformity with this law, Gay Lussac found that the vapours of alcohol and water mix like two gases which have no action upon one another. The density of the mixed vapours agreed closely with the density calculated according to Dalton’s law. In 1836 Magnus published an important memoir on the same subject. He found that, if two liquids which do not mix with one another are introduced into a barometer tube, the tension of the mixed vapours at any temperature is equal to the sum of the tensions of the vapours of the two liquids. But when the liquids have the property of mixing with one another the behaviour of their vapours he found to be altogether different. The tension of the mixed vapours was no longer equal to the sum of the tensions of each vapour separately. This statement appears at first view to contradict the experiments of Gay Lussac, but, as Magnus himself has pointed out, the conditions under which the observations of the two eminent physicists were made were essentially different. In the experiments of Gay Lussac the mixed liquids were wholly converted into vapour, and therefore the mixed vapours formed were not in contact with any liquid, while in those of Magnus an excess of the mixed liquids was always present, and in contact with the vapour,

scholarly journals The Bakerian lecture: On the gaseous state of matter

1876 ◽  
Vol 24 (164-170) ◽  
pp. 455-459 ◽  
Keyword(s):  
High Pressures ◽  
Carbonic Acid ◽  
Glass Tube ◽  
Gaseous State ◽  
Acid Gas ◽  
Original Memoir ◽  
Glass Tubes ◽  
The Mean ◽  
State Of Matter ◽  
Mean Time

After referring to certain modifications in his former method of working at high pressures, the author describes some preliminary experiments which were undertaken to determine the change of capacity in the capillary bore of the glass tubes under the pressures employed. From these experiments it appears that, on raising the pressure from 5 to 110 atmospheres, the capacity was increased for each atmosphere by only 0·0000036, and that this change of capacity was chiefly due to compression of the internal walls of the glass tube. Another set of experiments was made to ascertain whether air or carbonic-acid gas is absorbed at high pressures to any appreciable extent by mercury. For the method of operating and other details reference must be made to the original memoir; but the general result is that no absorption whatever takes place, even at pressures of 50 or 100 atmospheres. The pressures are given according to the indications of the air-manometer in the absence of sufficient data (which the author hopes will be soon supplied) for reducing them to true pressures. In the mean time it is probable, from the experiments of Cailletet, that the indications of the air-manometer are almost exact at 200 atmospheres, and for lower pressures do not in any case deviate more than from the true amount. In a note which was published last year in the ‘Proceedings’ of the Society (No. 163), it was staffed that the coefficient of expansion ( a ) for heat under constant pressure changes in value both with the pressure and with the temperature. The experiments on this subject are now completed, and are described at length in this paper. The final results will be found in the two following Tables. In the first Table the values of a are referred to a unit volume at 0º and under one atmosphere. In the first column the pressure p in atmospheres is in terms of the air-manometer.

scholarly journals On the velocity of sound in gases at high temperatures, and the ratio of the specific heats

1921 ◽  
Vol 100 (702) ◽  
pp. 1-26 ◽  
Keyword(s):  
Specific Heat ◽  
High Temperatures ◽  
Velocity Of Sound ◽  
Specific Heats ◽  
A Value ◽  
Mean Temperature ◽  
Considerable Experience

The experiments described in this memoir on the velocity of sound in gases, at temperatures varying from atmospheric to that of a bright red heat, were made with the object of tracing the change in the specific heat of gases with rising temperature, and, if possible, of arriving at formulæ which might be applicable to the extremely high temperatures reached in explosions. The sound method was decided on chiefly for the reasons (1) that the velocity of sound in a heated gas gives a value for the ratio of the two specific heats at the temperature of the experiment, and not as in the method of mixtures at a mean temperature between the highest and lowest point of the heated and cooled gas; and (2) because we had had considerable experience in the use of a chronograph for measuring the rapid movements of flame through gases in long tubes. It is necessary to make it clear at starting that no claim is made that these experiments give more exact determinations of the specific heat of gases than those given previously by experiments over low ranges of temperature; the object has been to obtain by comparative measurements the general gradients of the curves rather than to find the exact value at any definite point.

scholarly journals On a new compound of chlorine and carbon

1833 ◽  
Vol 2 ◽  
pp. 153-153
Keyword(s):  
Carbonic Acid ◽  
Chemical Properties ◽  
Glass Tube ◽  
The Other ◽  
Physical And Chemical Properties ◽  
Rock Crystal ◽  
Acid Gas ◽  
Green Glass ◽  
Physical And Chemical ◽  
And Chemical Properties

The above substance was discovered by M. Julien, of Abo, in Finland, amongst the products arising out of the distillation of calcined sulphate of iron, with crude nitre in iron retorts. It forms white acicular crystals by sublimation, and when passed through a green glass tube containing red-hot rock crystal, it is decomposed with the deposition of charcoal and evolution of chlorine. It is not altered by repeated sublimations in chlorine. It was analysed by passing its vapour over red-hot oxide of copper, by which chloride of copper and carbonic acid gas were produced: the former was de­composed by nitrate of silver, and the proportion of chlorine esti­mated by that of chloride of silver formed. From this and other experiments, the authors conclude that this substance consists of one portion of chlorine and two of carbon: they failed in their endea­vours to convert it into either of the other chlorides of carbon, to which, in its physical and chemical properties, it bears however a considerable resemblance.

THE SPECIFIC HEATS OF MAGNESIUM, CALCIUM, ZINC, ALUMINUM AND SILVER AT HIGH TEMPERATURES

1924 ◽  
Vol 46 (5) ◽  
pp. 1178-1183 ◽  
Author(s):  
E. D. Eastman ◽  
A. M. Williams ◽  
T. F. Young
Keyword(s):  
High Temperatures ◽  
Specific Heats

A METHOD FOR ADIABATIG COMPRESSION OF GASES UNDER CONTROLLED CONDITIONS

1960 ◽  
Vol 38 (12) ◽  
pp. 2482-2487 ◽  
Author(s):  
G. D. Graham ◽  
O. Maass
Keyword(s):  
High Temperatures ◽  
Experimental Technique ◽  
Pressure Range ◽  
Specific Heats ◽  
Controlled Conditions ◽  
Preliminary Account

A preliminary account is given of an experimental technique by means of which the specific heats of gases may be measured at high temperatures and pressures. With the transducer employed consistent results were obtained up to 7000 p.s.i. and it is proposed to incorporate a transducer having a much higher pressure range where it is estimated that temperatures up to 10,000 °K can be recorded.

scholarly journals Some researches on flame

1833 ◽  
Vol 2 ◽  
pp. 59-61 ◽  
Keyword(s):  
High Temperature ◽  
Glass Tube ◽  
Platinum Wire ◽  
The Wire ◽  
Humphry Davy ◽  
Lower Temperature ◽  
Sulphuretted Hydrogen

This communication is subdivided into four sections, of which the first treats of the effect of rarefactions of the air, by diminished pressure, upon flame, and explosion. An inflamed jet of hydrogen was placed in the receiver of an air-pump, and the flame was observed to enlarge during exhaustion, till the gauge indicated a pressure of one fourth or one fifth; it then diminished in size, but was not extinguished till the pressure was reduced to between one seventh and one eighth. A somewhat larger jet burned until the rarefaction amounted to one tenth, and rendered the glass tube whence the gas issued white hot. To this circumstance the author refers the long-continued combustion of the gas, and thinks the conclusion confirmed by the following experiment. A platinum wire was coiled round the jet tube, so as to reach into and above the flame, and it became white hot during the exhaustion, and continued red hot even when the pressure was only one tenth. The lower part of the flame was now extinguished, but the upper part in the contact of the wire continued to bum till the pressure was reduced to one thirteenth. The flame, therefore, of hydrogen is extinguished in rarefied atmospheres, whenever the heat it produces is insufficient to communicate visible redness to platinum wire. Sir Humphry Davy was thus led to infer, that those combustibles which require least heat for combustion would burn in rarer atmospheres than those requiring more heat; and that bodies which produce much heat in combustion would burn in rarer air than those producing little heat, and experiments are detailed proving this to be the case: thus, an inflamed jet of light carburetted hydrogen, which produces little heat in combustion, and requires a high temperature for its ignition, was extinguished whenever the pressure was below one fourth, even though the tube was furnished with a wire. Carbonic oxide burned under a pressure of one sixth; sulphuretted hydrogen of one seventh. Sulphur, which burns at a lower temperature than any other ordinary combustible, except phosphorus, had its flame maintained in an atmosphere rarefied 15 times, and phosphuretted hydrogen was inflamed when admitted into the best vacuum of an excellent air-pump. The author next proceeds to consider the influence of rarefaction, produced by heat, upon combustion and explosion. A volume of air at 212° is expanded to 2·25 volumes. At a dull red heat its probable temperature then is 1032°, provided it expand equably for equal increments of heat.

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