Velocity of Sound in Liquid Oxygen

Abstract

IT seems that the velocity of sound has never been measured in liquefied gases at low temperatures, probably because the customary methods were not easily practicable. It appeared reasonable to try as a new method the effect, which has recently been discovered by Debye-Sears and Lucas-Biquard, namely, the scattering of light by ultrasonic waves in liquids and solids. Judging from the results which I have obtained using oxygen as a scattering liquid, this method provides indeed a simple and convenient means for this purpose. The experiments, which were carried out with oxygen of 99·3 percent purity, boiling at atmospheric pressure (705–720 mm. mercury) at – 183·6° C., and with a frequency of 7,500 kilocycles, yielded a sound velocity of 903 m./sec. Taking 1·140 as the density of the liquid, one gets then an adiabatic compressibility of 105·6 × 10⁶ cm.²/kgm. The isothermal compressibility may also be calculated; with 3·38 × 10³ as the value of the differential of the specific volume, and 0·406 as the specific heat at constant pressure, it comes out as 172·0 × 10⁶ cm.²/kgm.