Discussion Overview
The discussion revolves around calculating the absolute third law entropy of a gas solution containing methane and ethane at 25°C and 1 atm. Participants explore the application of the mixing entropy equation and the relevance of absolute entropies of the individual gases in this context.
Discussion Character
- Homework-related
- Mathematical reasoning
- Technical explanation
Main Points Raised
- One participant proposes using the equation dSmix = -nR(x1lnx1 + x2lnx2) to calculate the mixing entropy, questioning the necessity of the absolute entropies of methane and ethane in this calculation.
- Another participant clarifies that the absolute entropies of the gases are not useless, as they contribute to the total entropy calculation when mixed.
- A participant expresses confusion regarding the summation of entropies for unmixed gases and seeks clarification on the concept of extensive quantities.
- There is a reiteration that the total entropy for unmixed gases is the sum of their individual entropies, which is a fundamental property of extensive quantities.
Areas of Agreement / Disagreement
Participants exhibit some disagreement regarding the role of absolute entropies in the mixing entropy calculation, with no consensus reached on whether they are necessary for the solution.
Contextual Notes
Participants express uncertainty about the definitions and implications of mixing entropy and absolute entropy, indicating potential limitations in understanding the relationship between these concepts.