As an expert in thermodynamics, I can explain the concept of reversible and irreversible work. In thermodynamics, work is considered as a transfer of energy that occurs when a system undergoes a change in volume, usually against an external pressure. The distinction between reversible and irreversible work is crucial for understanding the efficiency of thermodynamic processes.

Reversible Work is an idealized concept where the work done by a system is such that the system can be returned to its initial state without any net change in the system or its surroundings. This type of work is associated with a quasi-static process, where the system is always in equilibrium with its surroundings. The system and the surroundings are in a state of infinitesimally slow change, allowing for the process to be reversed at any point without any energy loss.

Irreversible Work, on the other hand, occurs in real-world processes that are not perfectly controlled. These processes are characterized by rapid changes and are not in equilibrium with the surroundings at every step. Because of this, some energy is inevitably lost to the surroundings as heat, which cannot be completely recovered. This is why irreversible work is considered less efficient than reversible work.

The reference to "All real processes are irreversible" highlights the practical nature of thermodynamic processes. In reality, no process is completely reversible due to various factors such as friction, turbulence, and finite rates of change. When a process is carried out slowly, more work can be extracted from it because there is less heat loss to the surroundings. This is because the system has more time to reach equilibrium at each step, reducing the entropy change and making the process closer to being reversible.

The statement about a reversible process being influenced by a "very small increase in the external pressure" refers to the sensitivity of the system to external conditions. In a reversible process, the system is in such a delicate balance that even a minor change in external conditions can cause the system to deviate from its intended path, indicating the fine line between reversible and irreversible processes.

In summary, the efficiency of a thermodynamic process is directly related to its reversibility. The more reversible a process is, the more work can be extracted from it, and the less energy is wasted as heat. Irreversible processes, by their nature, are less efficient due to energy losses that cannot be recovered.

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All real processes are irreversible. If a process does work on the surroundings, you get more work out of the process if it is done slowly. This is because less heat is lost to the surroundings. ... This is a reversible process because a very small increase in the external pressure would cause the gas to be compressed.read more >>