Page:Popular Science Monthly Volume 73.djvu/63

Rh to have contained: but, until a loss of copper be ascertained, to correspond with the gain in lithium, it appears to me that the assumption of transformation is premature. Ramsay found that this solution contained in all 1.67 mg. alkaline chlorides, chiefly sodium chloride; while 0.79 mg. were produced in a blank experiment, when the emanation was excluded. While this latter amount is admittedly derived from the glass bulb, the excess obtained in the presence of emanation is ascribed to the degradation of the copper, neglecting the fact that this second solution must have been fairly acid and would, therefore, have attacked the glass more vigorously. Accepting his suggestion, however, the deficit of copper ought to approach 0.8 mg., an amount which ordinary analysis can detect. We may, therefore, hope that further experiments by Professor Ramsay will throw light upon this side of the subject.

Of Ramsay's present conclusion, the following resume may be given: Emanation is a gas of about atomic weight 216.5, derived from radium, of atomic weight 225, simultaneously with a-particles which are not helium. When emanation and the a-particles are shut up together, the bombardment of the latter breaks up the emanation into helium; but if heavier molecules, like water, be present, they receive some of the bombardment, and the emanation is only degraded into neon; the pressure of copper nitrate still further protecting the emanation, so that it only breaks clown to argon. This kinetic explanation is not impeccable; for, according to the principles of mass-action, the preponderance of water molecules in the copper nitrate solution, as well as the predominance of hydrogen and oxygen in its decomposition products, would imply the presence of considerable amounts of neon to accompany the argon. As neon is said to be absent, we must either seek for some other hypothesis or explain how the neon reverts to argon after it is once formed.

Ramsay's views contradict those of Rutherford and others, who seek to identify helium with the $$\alpha$$-rays, and the latter would thereby lose a good deal of their substantive character. Furthermore, it is to be noted that the $$\alpha$$-particles bear positive charges: if they were merely chemical atoms, such a charge might possibly be obtained as they tore themselves loose from the larger complex, during radiation; but if they be non-substantive masses of free energy, it will be difficult to reconcile the various assumed transformations with the electro-chemical properties, valencies, etc., of the elements in question.

It must be recalled that Rutherford does assume that the successive transformations of radium, for instance, are effected by the expulsions of the $$\alpha$$-particles and that these have atomic mass: an atom of radium, therefore, contains a finite number of them. As the transformations are atomic and not molecular, Rutherford's application of the mathematics of mass-action can mean but one thing: that the various rates of transformation depend upon the chances of encounter and relative