VIII. The combining volumes of hydrogen and oxygen

• Published in: Philosophical transactions of the Royal Society of London. Series A, Containing papers of a mathematical or physical character Vol. 216; no. 545; pp. 393 - 427
• Main Authors: Burt, F. P., Edgar, E. C.
• Format: Journal Article
• Language: English
• Published: London The Royal Society 1916
• ISSN: 0264-3952; 2053-9258
• DOI: 10.1098/rsta.1916.0008

The measurement of the combining weights of hydrogen and oxygen has been the subject of so many researches of a high order of excellence that any fresh investigation of this fundamental constant must be submitted with considerable diffidence. Nevertheless, it must be noted that the results obtained by various observers differ appreciably. According to Clarke (1), the values obtained by Morley and Noyes, by reason of the accuracy of their methods and the close concordance of the individual determinations, outweigh the results of all other investigators. The atomic weight of oxygen being 16, that of hydrogen, according to Morley(2), is 1˙00762, and according to Noyes (3), 1˙00787. (Clarke, on Noyes’ data, prefers the value 1˙00783.) It is, further, a significant fact that the arithmetic mean of all determinations discussed by Clarke, lies between these two values, which differ by 1 part in 4000. Both values are based on the gravimetric synthesis of water and are independent of a knowledge of the densities of the gases. A physico-chemical method of determining the relative molecular weights depends on the knowledge of the ratio of the densities, together with that of the combining volumes.