Speed of sound in NaCl, MgCl₂, Na₂SO₄, and MgSO₄ aqueous solutions as functions of concentration, temperature, and pressure Available to Purchase

The speeds of sound in aqueous solutions of NaCl, MgCl₂, Na₂SO₄, and MgSO₄ have been measured relative to pure water from 0 to 1 molal ionic strength, 0° to 55 ° C, and 0 to 1000 bar applied pressure. The 1‐atm results have been fitted to polynomial equations of concentration and temperature with standard deviations of about 0.1 m/s, U⁰−U_W⁰=am+bm^3/2+cm² where U₀ and U_W⁰ are the 1‐atm sound speeds in solution and in pure water, respectively; m is molality; and a,b, and c are temperature‐dependent parameters. The effect of pressure on the relative speeds of sound has been fitted to equations of the form (U^P−U_W^P)−(U⁰−U_W⁰) =dm+em^3/2+fm², where U^P and U_W^P are the sound speeds of the solution and water at applied pressure P and d,e, and f are temperature‐ and pressure‐dependent parameters. The standard deviations of the least‐squares fits are within 0.12 m/s for all the salts.