Question

A system in thermodynamic equilibrium satisfies the following requirements:

• A. A system is in mechanical equilibrium
• B. A system is in mechanical equilibrium and chemical equilibrium
• C. A system is in mechanical equilibrium and thermal equilibrium
• D. A system is in mechanical equilibrium, chemical equilibrium and thermal equilibrium

Hint:

Note that a system must be in mechanical, thermal and chemical equilibrium simultaneously to reach the thermodynamic equilibrium. If any of the equilibriums is not met, the system cannot be in the thermodynamic equilibrium.

Answer 1

The Correct Option is D

Thermodynamic equilibrium denotes a state where a system's macroscopic properties remain constant over time. This state is achieved when a system balances its energy and matter exchange with its surroundings and internal components. Three primary equilibrium types define these aspects:
• Mechanical Equilibrium: No net forces act on the system or its parts, implying no pressure gradients. In closed systems, pressure is uniform.
• Chemical Equilibrium: The system's chemical composition remains unchanged; the net rate of all chemical reactions is zero, preventing further net conversion between reactants and products.
• Thermal Equilibrium: The system's temperature is uniform internally and matches its surroundings, eliminating further net heat exchange.
Achieving full thermodynamic equilibrium requires satisfying all three conditions concurrently.