Biographical Memoirs Volume 44 (1974) / Chapter Skim
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8. Theodore William Richards
8. Theodore William Richards
Pages 255-291
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Hill. Restoration of the potassium effect by means of action currents.
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{.G.P., 20:685-93. Electrochemical methods in the study of plant cells.
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Biol., 8: ~ 1-52. 1941 Cold Spring Harbor Symp.
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J.G.P., 26:65-73. J.G.P., 26:2931944 Studies of the inner and outer protoplasmic surfaces of large plant cells.
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Sci., 35:548-58. Extrusion of jelly by eggs of Nereis limbata under electrical stimulus.
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~.G.P., 35:579-94. Activation of eggs of Nereis limbata by a surface active extract of dead sperm.
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Annual Review of Plant Physiology, 8:1-10.
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T Richards had established his reputation as a landscape painter said, "He amazed me by getting married and resigning his position as designer fin a local firm manufacturing gas fixtures]
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In an article prepared for a Swedish journal shortly after he was awarded the Nobel Prize in 1915, Theodore Richards paid tribute to his understanding mother and father: "Although my parents had no experience with scientific investigation, their tastes and education having been of a very different kind, nevertheless they entered fully into the spirit of my desire to undertake it, and were wise enough to see that a possible future lay ahead for me in the path which so profoundly interested me. From that time my father always advised me to devote myself as much as possible to research.
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"There was nothing of the pose of his craft about him," writes his biographer, "the cast of keen observation in his face, and the easy grace of his carriage, denoted the man of original thought and unconstrained opinion, the artist who sees a little deeper into objective life than most people, and whose instincts are, therefore, less confined to convention.... He knew he could draw matchlessly, and yet there were elements in the portrayal of a breaking wave that he never achieved to his own satisfaction.
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What reigning light Thine eyes discern in that surrounding night Whence we have come, what law that supersedes The fiat of all oracles and creeds, Thy soul will never find that Wrong is Right; At Christmas 1880, when Richards was not quite thirteen, chemistry had entered his life. He was given a large box containing materials and apparatus for 200 experiments "warranted to be safe and instructive." Richards has recorded his progress
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In the same year Richards printed three other papers based on his independent work on the atomic weights of copper and silver, as well as one dealing with the heat produced by the reaction of silver nitrate with solutions of metallic chlorides. Four publications and the young investigator was not yet twenty-one!
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He admired them and their way of life. It is altogether fitting that the definitive account of his life is the Theodore William Richards Memorial Lecture delivered by Sir Harold Hartley before the Chemical Society of London on April 25, 1929.
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graduate students, the professorship of physical chemistry which involved giving a full course of lectures, and the privilege of continuing a half course of lectures on "Elementary Theoretical and Physical Chemistry, including the Historical Development of Chemical Theory." This course he had initiated in the 1890s when he was still an assistant professor. These teaching tasks Richards thoroughly enjoyed because he did them well.
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The health of both father and mother was somewhat precarious but the duties of the professor of physical chemistry were carried out without fail year after year. Only for half a year in 1907 did Richards absent himself from Cambridge in order to function as the Exchange Professor at Berlin.
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The first of these categories includes the study of atomic weights, the second, the investigation of various problems concerning chemical equilibrium, the third, original work upon chemical thermodynamics both practical and theoretical, the fourth, the study of various problems in electrochemistry, and the fifth both practical and theoretical work concerning the significance of atomic compressibility and the changes exhibited by atomic volumes under varying conditions. During the past twenty-six years Richards has been directly concerned in the study of the atomic weights of twenty elements, and some of his pupils at Harvard have independently studied ten more.
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The relation of copper to silver, of copper to bromine, and of copper to sulphuric acid were all determined with care, and all yielded essentially the same new value, thus leaving no doubt that the old value for copper was nearly one-half a percent too low. The anomalous behavior of barium sulphate led Richards then to study the atomic weight of barium; both barium chloride and barium bromide were analyzed taking care to drive off all
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The investigation upon caesium marked the end of the first period of his investigations concerning atomic weights— the time during which the work of Stas had been considered impeccable. In 1904 the investigation of a large number of specimens of sodium bromide while verifying Stas's atomic weight for bromine seemed to indicate that this value for sodium was distinctly too high.
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The most recent finished problem with which he has been concerned was a study of the atomic weights of lithium, and silver. Not only was the ratio of lithium chloride to silver determined but also its ratio to silver chloride and besides this by a new method the amount of lithium chloride contained in lithium perchlorate was carefully determined.
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This seems to have been Stas's most grievous error, and came to pass only because all the defects in his process accumulated on the head of this lightest of all the metals. Richards has himself said that "the secret of success in the study of atomic weights lies in carefully choosing the particular substances and processes employed, and in checking every operation by parallel experiments so that every unknown chemical and physical error will gradually be ferreted out of its hiding place.
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With the help of pupils, he has applied this method to the determination of the specific heats of solids at low temperatures, the specific heats of liquids, the heats of solution of metals in acids, and the heats of combustion of organic substances, having obtained a great variety of data upon these various topics, many already published and
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His study of heat capacities, however, was not limited to the practical laboratory work. In a paper, which deserves especial mention because it has been frequently overlooked, he pointed out on the basis of such data as were available at that time that the change of heat capacity of a reacting system was In all probability connected with the difference between the total energy change and the free energy change in that reaction.
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His electrochemical work has also included the determination of single potential differences as well as of the electromotive forces exhibited by dilute and concentrated liquid amalgams. The most interesting contribution to the former class of phe
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The work upon the significance of changing atomic volume and atomic compressibility which has occupied much of Professor Richards's time during the last thirteen years has both a practical and a theoretical aspect. His views concerning the nature of the liquid and solid state have led him to make a large number of determinations of compressibility, of surface tension, and heat of evaporation, which have enriched considerably our knowledge upon this subject, and which cannot but be of lasting value, even independent of any hypothesis.
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He reasoned that if b is changeable, the actual size of the molecules to which b is probably nearly related must also be changeable. This implies molecular compressibility, and if molecules are compressible, they must be much compressed by the great forces of cohesion and chemical affinity which exist in solid and liquid substances.
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He has been able to show without much room for doubt that the reasons for the occasional deviations from the general rule, deviations which probably destroyed earlier confidence in the whole matter, are almost certainly due to the concomitant action of both chemical affinity and cohesion; in other words he by approximate quantitative evidence was able to show that not only the combination of atoms to make molecules causes compression, as the affinity is greater, but also that the molecules in cohering to one another in order to form a liquid or a solid compress one another in this process also. Hence the total volume of a liquid or solid appears according to his hypothesis to be the result of these varying and very different affinity-pressures.
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Thus a part of the effect which each new atom has on the affinities of the other atoms already present may be explained." He has published a number of papers upon the subject of atomic compressibility; the whole matter is summed up briefly in his Faraday Lecture of 1911. During the twelve years since his first publication upon the subject, no one seems to have been able to advance a first-rate argument against this theory of compressible atoms, and if it continues to gain ground, as it has during this period, one may safely predict that before long it is bound to cause nothing short of a revolution in the kinetic point of view concerning the nature of equilibrium and change in solid and liquid substances as well as a better understanding of the deviations of gases from the exact gas law.
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Chem. Zeitschrift fur anorganische Chemie (later, Zeitschrift fur anorganische und allgemeine Chemie)
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i., 15: 567-78. With Hubert Grover Shawl Cupriammonium double salts.
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J., 20: 189-95. A table of atomic weights.
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Arts Sci., 35: 123-50; Z physik.
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III. The relation of changing heat capacity to change of free energy, heat of reaction, change of volume, and chemical affinity.
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A revision of the atomic weights of sodium and chlorine.
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Shannon Forbes, Edward Mueller, and Grinnell tones. Further researches concerning the atomic weights of potassium, silver, chlorine, bromine, nitrogen, and sulphur.
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