ELEMENTS.
PART II.

By F. H. LORING.

We have seen that certain of the elements may have been evolved by a cyclic process, which, in its graphic representation, has been likened to a complex hysteresis loop, as shown by Prof. Ewing in his book on magnetic induction in iron, &c. (See Part I., CHEMICAL NEWS, cxi., 157). Referring to Fig. 3, we have now to consider the representation of the elements missed out in the completed diagram, since these are supposed to have been evolved separately, and to belong to another similar, but probably narrower, complex loop. Such a loop might in places describe the same paths as the one illustrated, and consequently involve the additional evolution of elements similar to those already shown.

It becomes difficult to trace out the tortuous course of this series of loops, but an attempt without resorting to a diagram may have some suggestive interest.

The first element of this new series may be lithium; that is to say, one of its component sets of associates, owing to the first loop possibly taking an early upward course just where the lower atomic weight associates would appear-if the line of evolution had continued, as shown in Fig. 3. What the spectrum of such an element might be we cannot say, but in all probability the very low atomic weight associates, if separated from their companions of higher or lower relative atomic weight, or separated from those of another complex cycle, would show some spectroscopic difference, and this may account for certain nebular lines observed: those which have not been reproduced or verified in the laboratory with known elements. We must not, by the way, forget that temperature also plays a part in these phenomena.

The next element would be helium, assuming that this narrow cycle has some subordinate loops which extend to the zero valency line.

Continuing this complex cycle, in which we will represent the higher atomic weight associates in heavy-face type and the corresponding lower ones in light-face type,

we have

Mg-Na-Ne-Ne-Na- Mg: Ca-K-Ar-Ar K-Ca : Fe-Ni-Fe-Ni-Cot: Pd-Pd-Rh-Rh: La-Ba-Cs-Xe-Cs-Ba-La-Cerium,

and the elements of the rare earths, followed by a side-loop taking iridium and platinum. Coming now

round on the reverse side of the cycle (below the horizontal zero line, say, on the right-hand side) we have Ta-W-Os-Os-W-Ta, if these members belong to this complex loop. We have to consider the valency sequence as reversed on the lower side.

It is exceedingly difficult to discuss satisfactorily the characteristics of this series of narrow loops, but it seems to suggest that the elements of this cycle were formed

The completion of the diagram shown by Fig. 3 in respect to the left-hand subordinate loops involves the inclusion of Au, Hg, TI, Pb, and Bi in the top loop, and of Sn, Sb. (Te), and I in the middle one along with those shown.

+ By the expression "complex loop or cycle" is meant a series of connected subordinate loops or offshoots.

t Italicised symbols are here introduced to indicate members which are possibly homogeneous in not being made up of associates or isotopes differing materially in atomic weight. This will be understood by referring to Fig. 3, where the two types are shown, though o the wider complex cycle.

would be even fewer.

Lithium proper appears in the more advanced stars, as if the first loop of Fig. 3 had completed itself and had continued on, which would be the case in the stellar evolution where nitrogen and oxygen appear.*

loop characteristic peculiar to this narrow complex cycle, The rare-earth elements seem to partake of the shortand these loops may be represented as a succession of small ones similar to those shown in Prof. Ewing's book highly contracted type. on p. 346, Fig. 157. The Fe-Rh-Ir- groups are of the

It is perhaps suggestive to study magnetic phenomena whilst keeping in mind the ideas here indulged in; but, of cousre, we must remember that a set of curves having certain hysteretic peculiarities might be obtained without recourse to electrical or magnetic circuits at all. It would seem, nevertheless, unnatural to get away from molecular or even electric influences, so that our analogy from these the atom to the molecule; indeed, some atoms are molepoints of view seems reasonable. It is only a step from.. cules, and the atoms themselves are electrically

constituted.

The question of duality in the atomic type, or the composite nature of the elements, is one to which radioactivity leads up, and Prof. Soddy's observation that there are chemically and electrically identical atoms, though differing in atomic weight, certainly finds extended verification amongst the many radio elements or radio-atoms, and such atoms or elements are impossible of separation by known means. On the other hand, there are identical elements in regard to atomic weight, yet having different electrical activities, and consequently chemical properties, and these are found to be quite easy of separation.

Sir William Crookes's early suggestion that our relative atomic weights may turn out to be mean numbers seems on the point of verification, to some considerable extent at least. We are, of course, familiar with his conception of meta-elements.

The discovery by Sir J. J. Thomson of a companion gas to neon having an atomic weight of 22 and existing in small relative quantities to neon of atomic weight 20 is highly suggestive, since ordinary composite neon of mean atomic weight 2012 may be made up thus:

20 X 10 = 200 22 X I = 22

II) 222

20.18

The mean value is close to the experimental one, and, moreover, Fig. 3 naturally accommodates these two metaelements or associated atoms, which have been designated neon and meta-neon.

Passing to the other end of the loop we have chlorine, which may be also composite, thus:

35 X 10 350 40 X I = 40

11) 390

35'454

There is a peculiarity in the early part of the other curve, as shown by Fig. 3, which would seem to point to an element of about atomic weight 3, but this may be a beryllium associate or satellite, unless we consider Hg as a pseudo-element and assign it to this place.

182

The experimental value in this example is 74'96, which is very close to the figured one, considering the magnitude of the number involved.

The question now might be raised, Are we sure that H, C, N, O, and F are practically whole-number or integer elements? The experimental evidence that such is the case is overwhelming with regard to every one of these elements except fluorine. A method of co-ordinating certain elements has been devised which involves taking the atomic weights of these elements as practically whole numbers, thus bringing all four or five members, including fluorine, into harmonious relationship. The method consists in arranging certain elements in quaternian series; for the full development of this method, see CHEMICAL NEWS, 1913, cvii., p. 95; cviii., pp. 188, 247, and 305. It is only fair to remark that this special treatment is punctuated with some uncertainties, but the above-mentioned elements are in satisfactory accord.

We will now consider the adverse side of the problem by quoting from Sir J. J. Thomson's "Atomic Theory," page 10:"By means of the electric spectrum [positive ray method] we can prove in a very direct and striking way some of the fundamental truths about the Atomic Theory. For example, when we form the electric spectrum of a mixture of gases, such as the air, we get a limited number of sharply-divided streams, which show no tendency to merge into each other. This shows that the gas contains only a few kinds of particles, and that all the particles of one kind have exactly the same mass, for if there had been any variation in the masses the streams would have been fuzzy. This shows that all the atoms of an element are alike; this had sometimes been questioned, and it had been suggested that there might be considerable variation in the masses of the atoms of the same element; ordinary chemical analysis could not settle this question, for it gives nothing more than the average mass of billions of atoms."

On page 16, Sir J. J. Thomson goes on to say :"Since the atomic weights of the elements show that in their formation a measurable change of mass has taken place, the changes of energy involved in the formation of the elements must be enormous compared with those liberated in any chemical changes with which we are acquainted. Let us take an example:-The atomic weight of chlorine is 35'5; this is not a whole number; it differs from the nearest by half a unit; it follows, therefore, that in the formation of 35'5 grms. of chlorine there must have been a change of mass of at least half a grm. This involves the liberation or absorption of an amount of energy equal to that possessed by half a grm. moving

{CHEMICAL NEWT,

April 1915

with the velocity of light, i.e. 2.25 X 1020 ergs. This is about the amount of work required to keep the Mauretania going at full speed for a week, and must have been stored up or liberated from 35'5 grms., or about one ounce of chlorine. We see that changes in the atom large enough to change the chemical character of the atom-i.e., to split an atom of one element up into different kinds of atoms-involve enormous transformations of energy; in fact, the explosion of the atom in a few pounds of material might be sufficient to shatter a continent. We are living in the midst, nay, are made up of quiescent volcanoes; fortunately their slumbers are very sound."

When we consider that, so far as published accounts of positive-ray experiments extend (see "Rays of Positive Electricity," by Sir J. J. Thomson, 1913, Longmans, Green, and Co.), they are, except in the case of chlorine, practically confined to the very elements in our diagram which have of necessity no associates differing in atomic weight (apart from the two neons, which are in satisfactory agreement), we begin to wonder whether the explanatory theory Sir J. J. Thomson has applied to this element, by way of example, affords a fully correct interpretation of facts. We must hesitate about questioning so great an authority, but there are others in great authority who seemingly take a different point of view; at least Prof. Soddy's findings in radio-activity, and Sir William Crookes's idea of meta-elements, offer a different solution, as we have already seen.

We used the word "practically" in the foregoing paragraph because, adhering to our theory, some of the associates differ so little in atomic weight that they would not in all probability give a separate and distinct positiveray line on the photographic plate. In fact, Sir J. J. Thomson says on page 54 in his book cited :-. "As m/e for this atom is 27.5, and for the nitrogen molecule 28, the lines would be so close together that it would be difficult to differentiate them." Take argon, for instance, having associates or isotopes of atomic weight 39 and 40 (ratio, say, 1:10). These would give very close lines on the plate. There is another consideration, however, in this case. The "40" line might be confused with the neon one, as, assuming that the "40" line represents a particle carrying two charges, it might then be taken for neon with one charge, presupposing that no other determining feature enters into the experiment. This observation seemingly applies also to the "40" line of chlorine. Radio-activity has revealed atoms of identical atomic weight but of different electrical composition or active constitution, therefore chemically different, so that the two 40's need not represent a real difficulty, assuming that they have a real existence. Referring to Fig. 3, it will be seen that their formation is represented to take place at widely separated times or places.

It is certainly extraordinary to consider a gaseous element like chlorine as having two sets of atoms differing by five units from each other, and co-existing in a ratio of 1 to 10, yet radio-activity gives almost such a case in the mixture of the radio-gas-atoms, and Fleck's experiments on condensation (Phil. Mag., 1915, xxix., p. 337) lead us to suppose that the thorium and radium emanations, or, in our minds, their component associates (CHEMICAL NEWS, 1914, cix., p. 241), are non-separable by condensation. Fleck cites Aston's failure to separate neon from meta-neon by fractional condensation (see Engineering, 1913, xcvi., p. 423). Aston appears, however, to have effected a separation by diffusion through a porous substance, which would suggest that the chlorine associates might be separated by some such method if they really exist. Be this as it may, evidently things are not quite as they seem, and electricity apparently conditions the atom in more ways than one.

The idea of extending the isotopes into the domain of ordinary elements (Soddy) is certainly supported by the argument of evolution of the chemical elements here given, and this, moreover, is founded mainly on the ideas advanced many years ago by Sir William Crookes.