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Ch.19 - Chemical Thermodynamics
Chapter 19, Problem 85

(c) How many reversible paths are there between two states of a system?

Verified step by step guidance
1
Understand that a reversible path in thermodynamics is a process that can be reversed by an infinitesimal change in a variable, such as pressure or temperature, without leaving any net change in the system and surroundings.
Recognize that in an idealized scenario, there are infinitely many reversible paths between two states of a system because you can change the state variables (like pressure, volume, and temperature) in infinitely small increments.
Consider that each reversible path represents a different way of transitioning between the initial and final states, with each path having its own unique set of intermediate states.
Acknowledge that in practical terms, reversible processes are an idealization and cannot be perfectly achieved in real systems due to irreversibilities like friction and heat loss.
Conclude that while theoretically there are infinite reversible paths, in practice, we often approximate these paths using quasi-static processes that are as close to reversible as possible.

Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Reversible Processes

A reversible process is an idealized thermodynamic process that can be reversed without leaving any change in the system or surroundings. In such processes, the system is always in equilibrium, and the path taken can be retraced in the opposite direction. This concept is crucial for understanding the efficiency of thermodynamic cycles and the maximum work obtainable from a system.
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State Functions

State functions are properties of a system that depend only on its current state, not on the path taken to reach that state. Examples include internal energy, enthalpy, and entropy. Understanding state functions is essential for analyzing thermodynamic processes, as they help determine the changes in energy and other properties between two states.
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Thermodynamic Paths

Thermodynamic paths represent the specific route taken by a system as it transitions from one state to another. These paths can be reversible or irreversible, and the number of reversible paths between two states is limited by the constraints of the system. Analyzing these paths helps in understanding the efficiency and feasibility of energy transformations in thermodynamic processes.
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