Research on the Atomic Weight of Oxygen
Edward Morley’s 1895 paper provides way to determine atomic weight, making chemistry less laborious and more precise.
Atomic weight values were vital for determining chemical composition, understanding novel reactions, calculating reacting quantities in industrial processes — in short, for virtually all operations in pure and applied chemistry.
In 1895 Edward Williams Morley provided scientists with a priceless tool that made all subsequent atomic weight calculations accurate. In a publication of the Smithsonian Institution, he introduced a new value for the atomic weight ratio of oxygen to hydrogen, providing the most precise determination of the atomic weight of oxygen ever. To this day, Morley’s investigation is regarded as the pinnacle of “wet-chemical” atomic weight measurements.
In 1895 Morley calculated his value for the relative atomic weight of oxygen (on the scale hydrogen = 1 exactly) as 15.879. He published the value in his magnum opus, “On the Densities of Hydrogen and Oxygen and on the Ratio of Their Atomic Weights,” which appeared in Smithsonian Institution Contributions to Knowledge, no. 980. Briefer versions were published in the American Chemical Journal, the Zeitschrift für physikalishe Chemie, and the Proceedings of the American Association for the Advancement of Science.
These publications revealed to the scientific community as elegant and highly significant body of work. Morley’s peers hailed his achievement by bestowing upon him the most prestigious awards in the profession.
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Excerpted with permission, National Historic Chemical Landmarks Program