Mixture law has been applied to rheochor and mixtures of associated solutes in associated solvents have been studied The values of R, for acetone in acetic acid show a close agreement with \(R_{obs}\). observed, while in methyl alcohol and ethyl alcohol the straight line mixture law seems to hold. The agreement between \(R_x\) and \(R_{obs}\) for acetic acid is hater in EtOH than in MeOH. The results for MeOH in ethyl alcohol also show that the mixture law is applicable. For the same solutes, the agreement between \(R^x\) and Robs in different associated solvents is in the order : acetic acid > EtOH > MeOH. With increase of temperature, the values of \(R_x\) and \(R_{obs}\) fall and apporach the \(R_{cala}\), as it is the value at the boiling point of the liquid.