Which substance has the highest standard molar entropy at 25°C?

Question

Quizplus · Accepted Answer

According to the third law of thermodynamics, the molar entropy of a pure crystalline substance at absolute zero temperature is zero. Therefore, the substance with the highest standard molar entropy at 25°C would be the one with the most disorder or randomness in its molecular structure. Among the given options, gas molecules are generally more disordered than solids or liquids. Option B, C₂H₄(g), represents a gas molecule with multiple atoms that can vibrate and rotate freely, resulting in a high degree of randomness and therefore a higher molar entropy value at 25°C compared to the other substances.

Which Substance Has the Highest Standard Molar Entropy at 25°C