Accession Number : AD0274814

Title :   EFFECTS OF PRESSURE AND DIELECTRIC CONSTANT ON SOUND ABSORPTION IN MAGNESIUM SULFATE SOLUTIONS

Corporate Author : HARVARD UNIV CAMBRIDGE MASS ACOUSTICS RESEARCH LAB

Personal Author(s) : FISHER,FREDERICK H.

Report Date : MAR 1962

Pagination or Media Count : 1

Abstract : The simple dissociation model proposed by Bies (J. Chem. Phys. 23:428, 1955) to explain acoustic absorption in MgSO4 solutions does not give a complete quantitative description of experimental results in aqueous and dioxane-water solvents at atmospheric pressure. An attempt was made to explore the reasons for the failure of Bies' theory by measuring acoustic absorption as a function of pressure in MgSO4 solutions with two values for the dielectric constant. At the high concentration used, 0.5 M, a change in the dielectric constant from D = 78.5 (water) to D = 56.5 (25% dioxane-water) was accompanied by negligible changes in the magnitude and pressure dependence of the absorption. This behavior, together with that observed by Bies at low concentrati ns and atmospheric pressure, is consistent with the existence of an intermediate reaction, before dissociation, which is responsible for acoustic absorption. Velocity as a function of pressure, and the relaxation frequency at atmospheric pressure, are given for the 25% dioxane-water solution. (Author)

Descriptors :   *ABSORPTION, *ACOUSTIC INSULATION, *SOLUTIONS(MIXTURES), *SOUND, CHEMICAL REACTIONS, DIELECTRICS, DIOXIDES, ETHYLENES, LIQUIDS, MAGNESIUM COMPOUNDS, PRESSURE, RELAXATION TIME, SULFATES, TEST EQUIPMENT, WATER

Distribution Statement : APPROVED FOR PUBLIC RELEASE