Sound velocity and attenuation in liquid sulfur have been measured at tempe
ratures from 80 degreesC in the super cooled state through the melting temp
erature (about 120 degreesC) to 200 degreesC under saturated pressure. The
measurements were performed with a pulsed phase sensitive technique at freq
uencies from 5 to 22 MHz. Accuracy of the sound velocity measurements was 0
.1%. A distinct feature in sound velocity was found near 159 degreesC where
sulfur experiences an equilibrium polymerization. However, neither dispers
ion in the sound velocity nor any appreciable change in sound attenuation w
as observed. Excess sound velocity (with respect to the monomeric liquid) w
as extracted from the data and used to estimate the extent of polymerizatio
n as a function of the temperature. Both quantities exhibit a similar power
law behavior with the exponent close to 0.77.