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person_random_normal
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how do we find change in entropy for two points on a P V diagram which are not an isotherm
The temperature at the initial state may not be the same as the temperature in the final state. So the path may not be totally isothermal. But you have the right idea.MexChemE said:Since the change in entropy of the system only depends on the initial and final states of the system, you can design an isothermal reversible process which goes from the intial point to the final point indicated by the diagram and easily calculate its ΔS. It will be the same even if the actual process you are studying is not isothermal or reversible.
Entropy is a measure of the disorder or randomness in a system. In thermodynamics, it is often described as the amount of energy that is unavailable for work in a closed system.
The change in entropy (ΔS) can be calculated using the equation ΔS = Q/T, where Q is the heat transferred and T is the temperature in Kelvin.
The change in entropy is affected by the amount of heat transferred, the temperature, and the system's physical state. It also depends on the type of process (e.g. isothermal, adiabatic, reversible) and the number of particles in the system.
The change in entropy is important because it helps us understand the direction and efficiency of processes. In any spontaneous process, the total entropy of the system and its surroundings increases.
The second law of thermodynamics states that the total entropy of a closed system always increases over time. This means that in any spontaneous process, the total entropy of the system and its surroundings will increase, or at least remain constant. Entropy provides a quantitative measure of this law.