scholarly journals II. On the atomic weight of glucinum (beryllium)

1883 ◽  
Vol 35 (224-226) ◽  
pp. 137-138 ◽  
Keyword(s):  
Specific Heat ◽  
Volatile Compounds ◽  
Atomic Weight ◽  
Vapour Density

In this paper the author shows that no conclusions with respect to the atomic weight of glucinum can be drawn from analogy of its com­pounds with those of other metals, and that this long-disputed ques­tion can only be decided by the specific heat of the metal or by the vapour-density of some of its volatile compounds. Two determina­tions of the specific heat have been made by Professor E. Reynolds and by M. Nilson, the former of whom obtained a result of about 0.6, and the latter only about 0.4.

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.

The specific heat of lithium from 20 to 300 °K: the martensitic transformation

1960 ◽  
Vol 254 (1279) ◽  
pp. 444-454 ◽  
Keyword(s):  
Martensitic Transformation ◽  
Specific Heat ◽  
Atomic Weight ◽  
Phase Region ◽  
Two Phase ◽  
Self Diffusion ◽  
Debye Temperatures ◽  
Order Of Magnitude ◽  
Two Phases ◽  
Heat Of Transformation

Measurements on lithium of atomic weight 6·945 are reported. A thermal study of the martensitic transformation showed a large specific-heat anomaly in the reversion region and a specific heat dependent upon thermal history in the two-phase region. The high-temperature end of the reversion anomaly shows time effects which suggest that the process here is controlled by a spectrum of activation energies of the same order of magnitude as that for self diffusion. With some assumptions the heat of transformation from hexagonal closepacked to body-centered cubic lithium is deduced to be about 14 cal/g atom and the Debye temperatures of the two phases at 60 °K are 390 and 371 °K respectively. The entropy at 298·15 °K is 6·95 ±0·04 cal/°K g atom.

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. Investigations of the specific heat of solid and liquid bodies

1864 ◽  
Vol 13 ◽  
pp. 229-239 ◽  
Keyword(s):  
Specific Heat ◽  
Atomic Weight ◽  
The Subject ◽  
Solid Bodies

In the first part the author discusses the earlier investigations on the specific heat of solid bodies, and on the relations of this property to their atomic weight and composition. In this historical report he gives a com­plete analysis of the various opinions published on the subject.

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 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 Notes on the application of low temperatures to some chemical problems: (1) Use of charcoal vapour density determination; (2) Rotatory power of organic substances

1908 ◽  
Vol 80 (537) ◽  
pp. 229-238
Keyword(s):  
Low Temperatures ◽  
Rotatory Power ◽  
Atomic Weight ◽  
New Method ◽  
Organic Substances ◽  
Nickel Carbonyl ◽  
Gas Laws ◽  
A Value ◽  
Vapour Density ◽  
Low Pressures

In a recent paper Barkla and Sadler describe the investigation of the penetrating power of the secondary Röntgen rays emitted by different elements, which they find to be dependent on the atomic weight of the element. The behaviour of nickel was found by those investigators to be abnormal, and could only be reconciled with the behaviour of other elements by assigning to nickel an atomic weight of 61⋅4, a value considerably higher than the accepted value, 58⋅7. We therefore considered it of interest to make some further determinations of the density of nickel carbonyl at low pressures (when it would approximately obey the gas laws) by the use of a new method of manipulation which enables greater volumes of vapour to be employed, while, at the same time, the accuracy of the weight of the nickel carbonyl used in each experiment was considerably improved.

On the atomic weight of glucinum (Beryllium). Second paper

1886 ◽  
Vol 39 (239-241) ◽  
pp. 1-19 ◽  
Keyword(s):  
Specific Heat ◽  
Royal Society ◽  
Atomic Weight ◽  
Carbon And Nitrogen ◽  
Periodic Arrangement

In a former communication which I had the honour of making to the Royal Society, I described a method of preparing metallic glucinum and of determining its specific heat. From my experiments I deduced the result that the atomic weight of the metal must be 13·6 ( circâ ) in order to agree with Dualong and Petit’s rule. It is well known that the position assigned to glucinum in the periodic arrangement of the elements requires an atomic weight of two-thirds the above number, or approximately 9, and that with the larger atomic weight it falls between carbon and nitrogen, and is entirely out of place.

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.

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.

Sign in / Sign up

Export Citation Format

Share Document