Sound absorption in sodium sulfate (1 atm) and sodium chloride (1–307 atm) solutions from 30 to 300 kHz

Sound absorption from 30 to 300 kHz has been measured at 25° with a 100‐liter titanium spherical resonator technique for 0.03 M $Na2SO4$ and 0.16 M NaCl solutions at 1 atm and for 0.58 M NaCl solutions at pressures from 1 to 307 atm. The results show that these solutions exhibit the same absorption as that for deionized water; that is, within experimental error these solutions exhibit negligible absorption. These results are in agreement with J. Acoust. Soc. Am. 26, 223 (1954), Kurtze and Tatum [Acustica 3, 33 (1953)], and the recent work of Gilligan and Atkinson [J. Phys. Chem. 84, 208 (1980)]. These results are important for understanding the relation of sound absorption to ion pairing in $MgSO4$ and NaCl solutions including seawater, especially as a function of pressure. [This research was supported by ONR, NSF, and ARPA.]