- #1
Bipolarity
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I asked a question on this forum a few days ago about the entropy change of the surroundings, and am grateful for the insight provided. However, something faulty in my conceptualization is preventing me from solving this problem.
Let's say you have a set processes shown in the following diagram, where each of the arrows indicates a reversible process for which q and w can all be calculated:
A --> B --> C --> D
Suppose that there is a direct path A-->D, but this path is irreversible and the heat of this process is unknown. However, this path is known to be isothermal.
The entropy change (of the system) in going from A-->D is simply the sum of the individual entropy changes (of the system) in each of the above steps (since entropy is a state function and since each step is reversible).
Now comes the confusing part:
The entropy change of the surroundings in going from A-->D is calculated by summing up the heat transferred to the surroundings in each of the individual steps, and then divided by the temperature of the isothermal process A-->D.
This confuses me greatly. I don't understand why this approach is used in calculating the surroundings' entropy change.
Perphaps someone more experienced in thermo can explain?
BiP
Let's say you have a set processes shown in the following diagram, where each of the arrows indicates a reversible process for which q and w can all be calculated:
A --> B --> C --> D
Suppose that there is a direct path A-->D, but this path is irreversible and the heat of this process is unknown. However, this path is known to be isothermal.
The entropy change (of the system) in going from A-->D is simply the sum of the individual entropy changes (of the system) in each of the above steps (since entropy is a state function and since each step is reversible).
Now comes the confusing part:
The entropy change of the surroundings in going from A-->D is calculated by summing up the heat transferred to the surroundings in each of the individual steps, and then divided by the temperature of the isothermal process A-->D.
This confuses me greatly. I don't understand why this approach is used in calculating the surroundings' entropy change.
Perphaps someone more experienced in thermo can explain?
BiP