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phyahmad
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my question is short simply why reversibility requires equilibrium?
I was studying mehran kerdarbook on statistical mechanics of particlesberkeman said:What research have you done about this question? Can you post links to your reading that led to this question? Thanks.
Where can I learn about boltzmann's H theorem?Chestermiller said:In irreversible processes, transport of mass, momentum and heat occur at finite rates, and these cannot be reversed for the system without also bringing about a net change in the surroundings. Mass transfer involves diffusion at finite rates. Momentum transfer involves viscous dissipation of mechanical energy to internal energy and involves finite viscous stresses at finite deformation rates. Heat Transfer involves heat conduction at finite temperature gradients. All of these involve entropy generation within the system, rather than entropy transport via heat flow across the boundary of the system.
Reversibility in chemical reactions refers to the ability of a reaction to proceed in both the forward and reverse directions. In a reversible reaction, the products can react to form the original reactants under suitable conditions.
Equilibrium is important for reversibility because it represents a state where the rates of the forward and reverse reactions are equal. At equilibrium, the concentrations of reactants and products remain constant over time, allowing the reaction to proceed in both directions without any net change.
No, a reaction cannot be truly reversible without reaching equilibrium. Reversibility inherently implies that the reaction can proceed in both directions, and this is only possible when the system is at equilibrium, where the forward and reverse reaction rates are balanced.
Thermodynamics relates to reversibility and equilibrium through the concepts of free energy and entropy. A reversible process is one that occurs with no net change in free energy and maximum entropy production. At equilibrium, the free energy of the system is minimized, and any deviation from this state would require an input or release of energy.
Catalysts play a crucial role in reversible reactions by lowering the activation energy for both the forward and reverse reactions equally. This helps the system reach equilibrium more quickly but does not change the position of equilibrium. Catalysts ensure that reversibility is maintained by facilitating the reaction in both directions.