(12c) Experimental Densities and Excess Volumes for the Binary Mixtures Benzene-Toluene, Benzene-Acetone and Toluene-Acetone at Various Temperatures and Atmospheric Pressure

Experimental density measurements for the binary mixtures toluene- benzene, acetone-benzene and acetone-toluene were measured from 20°C to 65°C at atmospheric pressure over the entire composition range. The samples were prepared gravimetrically with an electronic balance (Sartorius BP 160P) precise to ±0.1 mg with 0.1 mol fraction nominal increments. The sample compositions are estimated accurate to 0.2%. The densities were measured using a vibrating tube densimeter (Anton Paar DMA 58). With proper calibration, this densimeter is accurate to ±1.0x10-5 g/cm3. The densimeter was calibrated using degassed, distilled water and air over the temperature range of interest. From the density measurements, excess molar volumes were calculated and fitted to a Redlich-Kister type equation. Our measured pure component densities agree with values published in the literature within ±0.1%. Our excess molar volumes for the toluene- benzene mixture compare with literature values within ±20%. For the acetone-toluene mixture, our excess molar volume values compare with literature values within ±30%. The excess molar volume for the acetone-benzene mixture agrees with literature values within 40%. The percent deviations are large because the excess molar volumes for these mixtures are extremely small. The calculated excess molar volumes are negative for the acetone-benzene and acetone-toluene mixtures and positive for the toluene benzene mixture.