scholarly journals The specific heats of metals and the relation of specific heat to atomic weight. Part II

1903 ◽  
Vol 71 (467-476) ◽  
pp. 220-221 ◽  
Keyword(s):  
Specific Heat ◽  
Atomic Weight ◽  
Absolute Zero ◽  
Nickel Steel ◽  
Pure Aluminium ◽  
Specific Heats ◽  
Nickel Cobalt ◽  
Weight Part ◽  
The Mean ◽  
Atomic Heat

The following values have been obtained for the mean specific heats, of pure aluminium, nickel, cobalt, silver, and platinum, within the several limits of temperature indicated: From these results the specific heats at successive temperatures on the absolute scale have been calculated, and it appears that the assumption of a constant atomic heat at absolute zero is untenable. The mean specific heat of a sample of nickel steel, containing 36 percent, of nickel and having remarkably small dilatation, was found to be as follows.

scholarly journals VI. The specific heats of metals and the relation of specific heat to atomic weight.—Part III

1904 ◽  
Vol 203 (359-371) ◽  
pp. 139-149 ◽  
Keyword(s):  
Specific Heat ◽  
Atomic Weight ◽  
The Other ◽  
Influence Of Temperature ◽  
Specific Heats ◽  
Weight Part ◽  
Chemical Combination ◽  
Influence Of Temperature On ◽  
The Mean ◽  
The One

The law of Neumann assumes that when an atom enters into chemical combination it retains the same capacity for heat as when in the uncombined or elemental state. This generalisation is, however, based on the values observed for the mean specific heats of elements and their compounds between 0° and 100° C. Attention was directed in Part II. of this investigation to the great differences found in the influence of temperature on the specific heats of various metals, such as aluminium on the one hand, and silver or platinum on the other. The experiments now about to be described were undertaken with the object of ascertaining to what extent these differences persist in the compounds of such elements.

scholarly journals II. The specific heats of metals and the relation of specific heat to atomic weight.—Part II

1903 ◽  
Vol 201 (331-345) ◽  
pp. 37-43 ◽  
Keyword(s):  
Specific Heat ◽  
Boiling Point ◽  
Atomic Weight ◽  
Liquid Oxygen ◽  
Specific Heats ◽  
Pure Cobalt ◽  
Total Range ◽  
Weight Part ◽  
Cobalt And Nickel

In the Bakerian Lecture for 1900 (‘Phil. Trans.,' A, vol. 194, p. 233) it was shown that the specific heats of very pure cobalt and nickel, when compared at temperatures from 100°C. down to the boiling-point of liquid oxygen, — 182°.5 C., steadily approach each other and together tend towards a least value which is at present unknown. It was thought desirable to increase the number of determinations at successive points on the thermometric scale, and to extend the total range of the experiments so as to afford better data for calculation of the form of the curves. The following is an account of the results obtained.

scholarly journals XVII. On the atomic weight of glucinum (Beryllium)

1883 ◽  
Vol 174 ◽  
pp. 601-613
Keyword(s):  
Specific Heat ◽  
Volatile Compound ◽  
Atomic Weight ◽  
Normal Number ◽  
Vapour Density ◽  
Atomic Heat ◽  
Lothar Meyer ◽  
Free Metal

I. Introductory. Ever since the discovery of glucinum by Vauquelin, in 1798, its atomic weight has been a disputed matter amongst chemists. Its discoverer considered that its oxide was a monoide, an opinion which was however strongly opposed by Berzelius, who wrote the oxide Gl 2 O 3 and the atomic weight 13⋅7 (O=16). The researches of Awdejew and Debrayt again turned the scale in favour of the earlier view, and as an atomic weight of 9⋅2 suited the properties of the metal in the tables of periodicy constructed by MM. Mendeleef and Lothar Meyer, this atomic weight has, up to quite recently, been generally accepted by chemists. As a welcome confirmation to this came a determination of the specific heat of the metal by Professor E. Reynolds, J who found that for its atomic heat to be near the normal number 6⋅0, its atomic weight must be 9⋅2 and not 13⋅8. Almost immediately afterwards a second determination of the specific heat was made by MM. Nilson and Petterson, who, however, obtained a result agreeing not with the lower atomic weight hut with the higher. The reasons for these conflicting opinions are to be found—first, in the anomalous position of glucinum among the elements; secondly, in the difficulties which surround the preparation of even small quantities of the free metal in a tolerably pure condition; and thirdly, in the fact that no volatile compound of glucinum is known of which the vapour density might be easily determined.

scholarly journals VI.—Bakerian Lecture.—The specific heats of metals, and the relation of specific heat to atomic weight

1900 ◽  
Vol 194 (252-261) ◽  
pp. 233-255 ◽  
Keyword(s):  
Physical Properties ◽  
Specific Heat ◽  
Pure State ◽  
Atomic Weight ◽  
Melting Points ◽  
Specific Heats ◽  
The Subject ◽  
The Difference ◽  
Melting And Solidification ◽  
Cobalt And Nickel

The experiments recorded in the following pages were begun nearly five years ago, at a time when opinion was still much divided as to the atomic weight of cobalt and nickel. It seemed to me that it would be a step in advance if it could be settled which of the two is the greater, for while perhaps the majority of chemists represented the atomic weight of cobalt as greater than that of nickel, some still assigned to them both the same value, while Mendeleeff did not hesitate to invert the order by making Co = 58·5 and Ni = 59. After taking into account all the best evidence on the subject, it appears certain that the atomic weight of cobalt is greater than that of nickel, but the fact remains that the values differ from each other by an amount which is less than the difference between any other two well established atomic weights, the respective numbers being variously represented by different authorities as follows :— The object of my experiments, however, soon developed into a wider field, for it appeared that the results obtained with these two metals might be made the means of further testing the validity of the law of Dulong and Petit, inasmuch as temperatures at which the specific heats would he determined are not only very remote, hut about equally remote, from the melting points of these two metals. Both metals are now obtainable in a pure state, and after melting and solidification under the same conditions are presumably in the same state of aggregation. Their atomic weights, though not known exactly, are undoubtedly very near together, as are also the densities of the metals and other of their physical properties.

scholarly journals The specific heats of metals and the relation of specif heat to atomic weight.—Part III.

1904 ◽  
Vol 73 (488-496) ◽  
pp. 226-227 ◽  
Author(s):  
William Augustus Tilden
Keyword(s):  
Atomic Weight ◽  
Specific Heats ◽  
Weight Part

The object of the experiments, of which an account is given in thi paper, was to determine whether the atomic heats of the element entering into combination are preserved in the compound at al temperatures, previous results obtained by the author and other having shown that the specific heats of metals of small atomic weight such as aluminium, increase very rapidly with rise of temperature.

scholarly journals Atomic specific heats between the boiling points of liquid nitrogen and hydrogen. I.—The mean atomic specific heats at 50° absolute of the elements a periodic function of the atomic weights

1913 ◽  
Vol 89 (609) ◽  
pp. 158-169 ◽  
Keyword(s):  
Periodic Function ◽  
Specific Heat ◽  
Liquid Nitrogen ◽  
Low Temperatures ◽  
Liquid Hydrogen ◽  
Specific Heats ◽  
Boiling Points ◽  
Royal Institution ◽  
Series Of Experiments ◽  
The Mean

A method of determining the specific heat of substances at low temperatures was described in a paper on “Studies with the Liquid Hydrogen and Air Calorimeter,” also in the abstract of a lecture delivered at the Royal Institution entitled“ Liquid Hydrogen Calorimetry,” where the apparatus then used is illustrated. Continuing the use of the same method, but with some modification of the apparatus, the investigation has been extended to a large number of inorganic and organic bodies. In this later series of experiments, the measurements of the specific heats of materials by the liquid hydrogen calorimeter were made over a range of temperature from boiling nitrogen to boiling hydrogen, a fall of temperature of some 57° Abs.

scholarly journals III. On the specific heats of gases at constant volume. Part I. Air, carbon dioxide, and hydrogen

1891 ◽  
Vol 48 (292-295) ◽  
pp. 440-441 ◽  
Keyword(s):  
Carbon Dioxide ◽  
Specific Heat ◽  
Mean Value ◽  
Constant Volume ◽  
Specific Heats ◽  
Absolute Density ◽  
The Mean ◽  
The Absolute

In this first notice the specific heats, at constant volumes, of air, carbon dioxide, and hydrogen are treated over pressures ranging from 7 to 25 atmospheres. The range of temperature is not sensibly varied. It is found that the specific heats of these gases are not constant, but are variable with the density. In the case of air the departure from constancy is small and positive; that is, the specific heat increases with increase of the density. The experiments afford directly the mean value 0·1721 for the specific heat of air at the absolute density of 0·0205, corresponding to the pressure of 19·51 atmospheres. A formula based on the variation of the specific heat with density observed in the experiments ascribes the value 0·1715 for the specific heat at the pressure of one atmosphere.

THE SPECIFIC HEAT OF MANGANESE FROM 16° TO 22° K

1940 ◽  
Vol 18a (5) ◽  
pp. 83-89 ◽  
Author(s):  
R. G. Elson ◽  
H. Grayson Smith ◽  
J. O. Wilhelm
Keyword(s):  
Specific Heat ◽  
Liquid Helium ◽  
Temperature Region ◽  
Liquid Hydrogen ◽  
Specific Heats ◽  
Atomic Heat

A calorimeter is described for routine measurements of specific heats in the temperature region of liquid hydrogen and liquid helium. It is designed so that samples can be interchanged without disturbing the calibration of the thermometer, or the water equivalent of the calorimeter. The calorimeter has been used to measure the specific heat of manganese from 16° to 22° K. It was found that the atomic heat of this metal is given by the formula[Formula: see text]

II. Note on the atomic weight of glucinum or beryllium

1883 ◽  
Vol 35 (224-226) ◽  
pp. 248-250
Keyword(s):  
Specific Heat ◽  
Atomic Weight ◽  
Minute Quantity ◽  
The Difference ◽  
Atomic Heat

In the course of a paper by Professor Humpidge on the above subject, recently read before the Society, the author seeks to decide between the atomic weight 9·2 for beryllium, resulting from my comparison of the atomic heat of the element with that of silver and aluminium, and the value 13·8, arrived at by MM. Nilson and Pettersson by determination of specific heat.J The difference between the two possible atomic weights is so small, and the difficulties met with in attempting to prepare even a few decigrams of beryllium are so great, that both sets of experiments have been objected to on the ground, amongst others, that the metal employed was in all cases impure. My specimen admittedly contained a minute quantity of platinum, and the Proportion of known impurity in one of MM. Wilson and Pettersson's specimens reached 13 per cent. Unfortunately, Professor Humpidge's metal though claimed to be the purest yet prepared, is shown by analysis to be rather less pure than one of the specimens employed by Nilson and Pettersson, hence the experiments lately made known to the Society do not carry the inquiry beyond the point previously reached, save in one noteworthy particular, namely, that there appears to be a considerable, though irregular, rise in specific heat of the element as the proportion of impurity diminishes; but the value is still much below that required for the atomic weight 9·2. Thus for a specimen of beryllium which contained 13 per cent. of known of impurity Wilson and Pettersson obtained the specific heat 0·4084 between 0° and 100° C., and for a less impure specimen 0·425; while Professor Humpidge, in one of his experiments with a material that contained 6 per cent, of impurity, found the specific heat to be nearly 0·45 (0·4497). In all these cases corrections were applied which were believed to eliminate the effects due to the impurities known to be present—in part mechanically mixed with the metal and partly alloyed with it.

I. On the specific heats of gases at constant volume. Part II. Carbon dioxide

1894 ◽  
Vol 55 (331-335) ◽  
pp. 390-391 ◽  
Keyword(s):  
Carbon Dioxide ◽  
Specific Heat ◽  
Lower Limit ◽  
Liquid State ◽  
Thermal Effects ◽  
Constant Volume ◽  
Specific Heats ◽  
Absolute Density ◽  
The Mean ◽  
True Specific Heat

In the former experiments on this gas, recorded in the first part of this research, the highest absolute density at which the specific heat was determined was 0·0378. In the present observations the determinations of specific heat have been carried to densities at which the substance was partly in the liquid state at the lower limit of temperature of the experiments. Observations dealing with true specific heat, uncomplicated by the presence of thermal effects due to the presence of liquid, are limited by the density 0·1444. At this density the mean specific heat over the range, 12° C. to 100° C., is 0·2035.

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