Measurement of the universal gas constant R using a spherical acoustic resonator.
نویسندگان
چکیده
R. S. Davis We report a new determination of the Universal Gas Constant R: (8.314471 ±0.OOOOI4)J.mol1K1• The uncertainty in the new value is 1.7 ppm (standard error), a factor of 5 smaller than the uncertainty in the best previous value. The gas constant was determined from measurements of the speed of sound in argon as a function of pressure at the temperature of the triple point of water. The speed of sound was measured with a spherical resonator whose volume was determined by weighing the mercury required to fill it at the temperature of the tri~le point. The molar mass of the argon was determined by comparing the speed of sound in it to the speed of sound in a standard sample of argon of accurately known chemical and isotoptic composition.
منابع مشابه
Measurement of the Universal Gas Constant Using an Acoustic Resonator
Competition is a great motivator. The 1988 measurement of the universal gas constant R at NIST [1] was stimulated by an error made at a rival national metrology institute, Great Britain’s National Physical Laboratory (NPL). In 1976, a group at NPL reported a “new” value for the universal gas constant R that had a standard uncertainty of 8.4 ppm (1 ppm = 1 part in 10). The “new” value was 159 pp...
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ورودعنوان ژورنال:
- Physical review letters
دوره 60 4 شماره
صفحات -
تاریخ انتشار 1988