Word: hydrogen
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Dates: during 1930-1939
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Three short years ago the formula D20 would have been meaningless to chemists because there was no element corresponding to the symbol D. Now every chemist in the land knows that D2O means heavy water, that D is the symbol for the heavy isotope of hydrogen which Dr. Urey identified in the autumn of 1931 (TIME, Dec. 21, 1931) and subsequently named deuterium. Undoubtedly in considering last week's award the Swedish Academy took cognizance of the fact that no discovery in the physical sciences in recent years has stimulated more widespread research than...
...Urey's heavy hydrogen did not burst entirely unexpectedly upon the world, nor was its discovery in any way an accident. It was rather the result of ingenuity backed by sound logic. There were discrepancies in atomic weights. The oxygen atom should have weighed 16 times as much as the hydrogen atom, but it did not. Then it was found that oxygen had two isotopes* weighing 17 and 18 units respectively. Thus it began to seem more & more probable that hydrogen might also have one or more isotopes of its own. Birge of the University of California and Menzel...
Like the perturbations in planetary orbits that indicated the existence of a planet beyond Neptune, all this was evidence, not proof. Like the planet Pluto, heavy hydrogen had to be located. Dr. Urey knew that if its atoms had indeed a mass of two units, it would show spectrum lines of a predictable kind and position. The question was how to get the substance in sufficient concentration to show spectrum lines at all. It occurred to him that if liquid hydrogen were allowed to evaporate, the lighter atoms would pass off first, leaving the heavy ones in greater abundance. Hydrogen...
...near his home in Hungary and in one day obtained a half-pound of his acid. In March last year, Professor Walter Norman Haworth of Birmingham. England determined the vitamin's constitution, and in August he, and Swiss chemists in Zurich. independently synthesized Vitamin C from a ketonaldehyde and hydrogen cyanide. Now the pure substance is produced as colorless crystals in Swiss and British laboratories at 3¢ per gram...
...blocked the passageway from his patient's stomach into his intestines. This stricture caused food to remain unduly long in the stomach. The food fermented and formed, along with non-inflammable carbon dioxide, highly inflammable methane (which miners know as fire damp and farmers as marsh gas) and inflammable hydrogen disulfide, the gas which makes rotten eggs smell as they...