eng Ansari Education and Research Society Journal of Ultra Scientist of Physical Sciences April 2010 22 1 95 102 juc 904 article Ultrasonic and viscometric studies of Silymarin, Rifampicin in 1, 4 dioxane at 303 k A. N. Sonar (ansonar1968@rediffmail.com) 1 N. S. Pawar 2 Shri V.S. Naik Arts Com., And Science College, Raver, Pratap College, Amalner <p style="text-align: justify;">Ultrasonic velocity, density and viscosity have been measured for substituted heterocyclic drugs Silymarin, Rifampicin in 1, 4 dioxane at 303<sup> </sup>k.. The measurement have been perform to evaluate acoustical parameter such as adiabatic compressibility (bs), Partial molal volume (f<sub>v</sub>), intermolecular free length (L<sub>f</sub>), apparent molal compressibility (f<sub>k</sub>), specific acoustic impedance (Z), relative association (RA), salvation number(Sn), limiting apparent molal compressibility (f<sup>0</sup><sub>k</sub>), limiting apparent molal volume(f<sup>0</sup><sub>v</sub>) and their constant (S<sub>k</sub>,S<sub>v</sub>). The viscosity coefficient (A,B) evaluate by using johndole equation. These parameter throw the light on the solute-solvent interaction and solute-solute interaction.<br /> &nbsp;</p> https://ultraphysicalsciences.org/paper/904/ Ultrasonic velocity viscosity adiabatic compressibility.