Reversible and Irreversible Processes

  • Processes occur when there exists a driving force for a change of state between parts of the system or between the system and surroundings
  • If the driving force is finite, the process is irreversible, and if it is infinitesimal in magnitude, the process is reversible.
  • All spontaneous processes occurring in nature are irreversible.


Reversible Process

  • A reversible process is a process that can be reversed by means of infinitesimal changes in some property of the system without loss or dissipation of energy, and can be reversed without causing change in the surroundings.
  • Due to these infinitesimal changes, the system is in thermodynamic equilibrium throughout the entire process.
  • For the system to undergo reversible change, it should occur infinitely slowly due to an infinitesimal gradient.