Estimation of critical amplitudes of the correlation length by means of calorimetric and viscosimetric measurements

The anomaly in the heat capacities of the critical mixtures of nitrobenzene with hexane, or heptane, or octane is characterised. The critical amplitude of the heat capacity is used in combination with the two-scale universality factor to estimate the critical amplitude of the correlation length for the three mixtures. In addition, viscosity measurements for the nitrobenzene + octane system are made. These viscosity values and those obtained in a previous work for the other two systems were corrected in the critical region by means of the calculated values of the correlation length amplitude; the critical exponent thus determined are consistent with the accepted value, which testifies to the effectiveness of the proposed method for estimating the correlation length amplitude.