
• slow isothermal compression or expansion of gases (so that no temperature gradient is required
to transfer the heat into or out of the system)
• electrolysis (with no resistance in the electrolyte)
2.8.2 IRREVERSIBLE PROCESSES
In reality all the processes have some losses, which might be friction, heat losses, hysteresis, etc.
Hence, all real processes are irreversible. This does not mean that it is impossible for a system to
perform a cycle made up of irreversible processes but simply that the surroundings will have been
altered by the cycle having been performed. A number of common irreversible processes will be listed.
• friction between solids, ...