Turbidity in the binary fluid mixture methanol-cyclohexane

The turbidity of a near-critical binary fluid mixture, methanol-cyclohexane, has been carefully measured above its (upper) critical consolute point. These measurements covered the reduced temperature region 10^-5{10}^{{{-}}2}and allowed theoretical predictions for the critical exponents ν and γ to be verified. The amplitude{{ξ}}₀of the correlation length was also determined to be 3.24±0.2 A while{{τ}}₀was (6.9±0.1)×{10}^{{{-}}6}$ ${cm}^{{{-}}1}$. Our result for ${{ξ}}₀$ is compared with other experimental determinations, and when combined with ${{τ}}₀$ and coexistence curve data, is used to determine the ratio R=${{ξ}}₀$(${B}²$/${k}BTc{{χ}}₀)1/ 3=0.71₅±{}0.02₄ which is consistent with the prediction 0.65--0.67 from two-scale-factor universality.