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Guilherme Mazui

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What is the Difference Between Reversible and Irreversible?

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The main difference between reversible and irreversible processes lies in their ability to be restored to their original state and the directionality of the process.

Reversible processes:

  • Can be reversed to obtain the original state of a system.
  • Involve infinite changes in the system.
  • There is an equilibrium between the initial and final state of the system.
  • Maximum work is obtained in the process.
  • Almost infinite time is taken to complete the reaction.
  • Examples include frictionless movement, restrained compression or expansion, and energy transfer as heat due to infinitesimal temperature nonuniformity.

Irreversible processes:

  • Cannot be reversed to obtain the original state of a system.
  • Involve finite changes in the system.
  • There is no equilibrium in the system.
  • The work obtained is not maximum.
  • The time taken for the completion of the reaction is finite.
  • Examples include the flow of electricity through resistance and the expansion of a gas into a vacuum.

In summary, reversible processes can be retraced in a reverse direction, while irreversible processes cannot. Reversible processes are considered ideal, while irreversible processes are real and more commonly encountered in nature.

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  • What is the Difference Between Reversible and Irreversible?
  • Comparative Table: Reversible vs Irreversible

    • Comparative Table: Reversible vs Irreversible

    Here is a table comparing the differences between reversible and irreversible processes:

    Feature Reversible Process Irreversible Process
    Definition A process that can be retraced to its initial state without causing any change in the combined system and environment. A process that cannot be retraced to its initial state without causing a change in the combined system and environment.
    Steps Proceeds in smaller, quasi-static steps that maintain equilibrium. Proceeds in larger steps with a definite driving force required.
    Speed Slower. Faster.
    Work Less work is done because the process is carried out against a constant external pressure. More work is done because the process is carried out against a changing external pressure.
    Entropy Does not increase the total entropy at the end of the cycle. Increases the total entropy at the end of the cycle.
    Example Expansion and compression of a spring. A hot cup of tea left on its own to cool down.

    Reversible processes are slow and go through various smaller stages that maintain equilibrium, while irreversible processes are faster and go through larger steps with a definite driving force required. Reversible processes can be brought back to their initial state without causing any change in the combined system and environment, whereas irreversible processes cannot be brought back to their initial state without causing a change.

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    Guilherme Mazui

    Guilherme Mazui is graduated in journalism from the Federal University of Minas Gerais (UFMG) and a master's degree in Communication from the University of São Paulo (USP). In addition, he has experience in advertising writing and has worked as a content editor in several companies.