An-Najah Staff

Ultrasonic velocity and absorption as a function of temperature, concentration, and frequency (5–25 MHz) and shear viscosity as a function of concentration and temperature are reported for the binary mixture nitrobenzene‐n‐hexane in the homogeneous phase above T _c . For the observed absorption at critical concentration and critical temperature α _c /f ² vs f ^−1.06 yields a straight line as predicted by the dynamic scaling theory of Ferrell and Bhattacharjee [Phys. Rev. A 2 4, 1643 (1981)]. Also, the critical amplitudes of the thermal expansion and specific heat have been calculated using the two‐scale factor universality relation. The adiabatic coupling constant g is calculated and compared to the experimental value. In addition, the experimental values of α/α _c (where α is the absorption at critical concentration above the critical temperature) for nitrobenzene‐n‐hexane are compared to the scaling function F(ω*) and show a good agreement with the theory. Finally, the velocity for the system at the critical concentration above the critical temperature appears to decrease linearly with increasing temperature.