The Atomic Weight of Silver

Abstract

IN NATURE of Dec. 11, 1926, reference is made to the determination of the atomic weight of silver (Trans. Chem. Soc., 1926, p. 2510) by H. Brereton Baker and H. L. Riley, who, by determining directly the ratio Ag: O in pure silver oxide have obtained the value 107.864 ± 0.0013. This work, carried out with the greatest ingenuity and with care and exactitude such as has only been reached by Th. W. Richards and his school, is of cardinal importance. As I have the honour to be chairman of the Sub-Committee for Atomic Weights of the International Commission on Chemical Elements, I have perhaps the right, as well as the official duty, of offering a few critical remarks. I may be allowed to add that I have studied the literature of atomic weights for fifty years and I was the first to propose, in 1888, the adoption of O = 16 as the standard of atomic weights. A like proposal was made almost simultaneously by Venable in America, and, as is well known, this has become the established practice. As the atomic weights of elements cannot as a rule be determined directly in relation to oxygen, secondary standards are required, and the most modern work published by Richards and his school is being carried out by finding the ratios xAg: RClx or yAg: RBry, to determine the atomic weight of R.