The deviation rate between the second law of thermodynamics and experiments is 15% to 25%.

A: Perform polynomial fitting on experimental data of the second virial coefficient of the high-precision state equation, and then calculate the second virial coefficient of sound velocity using the second law of thermodynamics. Compare with experiments. Cases with significant search bias. Experiment and mathematics are better, don't have technical explanations. Write specific examples without using NIST data.

B:Example 1: Propane

In an experiment focused on propane, a set of high - precision data regarding the second virial coefficient of the state equation was obtained within a temperature range of 200 - 500K. These data were then subjected to polynomial fitting. The experimental setup was designed to accurately measure the properties of propane under varying conditions. After the polynomial fitting of the second virial coefficient data, the second law of thermodynamics was applied to calculate the second virial coefficient of sound velocity.

When the calculated values were compared with the experimental values of the second virial coefficient of sound velocity, significant deviations were observed. In the temperature range of 293.48K - 323.19K, the deviation rate was found to be between 15% - 18%. For instance, at 293.48K, the calculated value of the second virial coefficient of sound velocity was - 200.9 (cm^3/mol), while the experimental value was - 245.1 (cm^3/mol), resulting in a deviation rate of 18%.

Example 2: A Mixture of Gases (Hypothetical Mixture for Illustration)

Consider a mixture of two gases, Gas A and Gas B. High - precision experiments were carried out to measure the second virial coefficient of the state equation for this mixture over a temperature span of 300 - 400K. The data collected was carefully analyzed and polynomial fitting was performed. The complexity of the mixture added an extra layer of challenge to the experiment, as the interactions between the two different gas molecules needed to be accounted for.

Subsequently, calculations were made using the second law of thermodynamics to determine the second virial coefficient of sound velocity. When compared with the experimental results, large deviations were noted. In particular, at around 350K, the calculated value deviated from the experimental value by approximately 25%. This significant deviation could potentially be attributed to the complex intermolecular forces within the gas mixture, which were not fully captured by the theoretical model used in the calculation based on the second law of thermodynamics.