12-Tungstosilicic acid and potassium 12-tungstosilicate were synthesized and conductivities, densities and ultrasound velocities of their aqueous solutions were studied in the 283.15–303.15K temperature range at 5K intervals. Apparent molar volume and apparent molar isentropic compressibility of 12- tungstosilicic acid and potassium 12-tungstosilicate and isentropiccompressibility of the studied aqueous solutions have been determined from the experimental density and sound velocity data.
