An '''irreversible process''' is a process in which it is impossible to return both the system and its surroundings to its original state by reversing from process. For instance, a combustion engine transforms gasoline into engine exhaust and energy; however, no process can turn the engine exhaust and the energy transfered to the car cannot be transformed back into gasoline. Irreversible processes generally involve an increase in [[entropy]].
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An '''irreversible process''' is a process for which it is impossible to return both the system and its surroundings to its original state by reversing the process. For instance, a combustion engine transforms gasoline into engine exhaust and energy; however, no process can turn the engine exhaust and the energy transfered to the car cannot be transformed back into gasoline. Irreversible processes generally involve an increase in [[entropy]].
Causes of irreversible processes include friction, unrestrained fluid expansion, heat transfer, and mixing.
Causes of irreversible processes include friction, unrestrained fluid expansion, heat transfer, and mixing.