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Equality of forward and backward reaction rates, however, is a necessary condition for chemical equilibrium, though it is not sufficient to explain why equilibrium occurs. Despite the limitations of this derivation, the equilibrium constant for a reaction is indeed a constant, independent of the activities of the various species involved ...
Chemical equilibrium is a dynamic state in which forward and backward reactions proceed at such rates that the macroscopic composition of the mixture is constant. Thus, equilibrium sign ⇌ symbolizes the fact that reactions occur in both forward ⇀ {\displaystyle \rightharpoonup } and backward ↽ {\displaystyle \leftharpoondown } directions.
The equilibrium potential for an ion is the membrane potential at which there is no net movement of the ion. [1] [2] [3] The flow of any inorganic ion, such as Na + or K +, through an ion channel (since membranes are normally impermeable to ions) is driven by the electrochemical gradient for that ion.
a thermodynamic equilibrium constant, denoted by , is defined to be the value of the reaction quotient Q t when forward and reverse reactions occur at the same rate. At chemical equilibrium, the chemical composition of the mixture does not change with time, and the Gibbs free energy change for the reaction is zero. If the composition of a ...
At 298 K, a reaction with ΔG ‡ = 23 kcal/mol has a rate constant of k ≈ 8.4 × 10 −5 s −1 and a half life of t 1/2 ≈ 2.3 hours, figures that are often rounded to k ~ 10 −4 s −1 and t 1/2 ~ 2 h. Thus, a free energy of activation of this magnitude corresponds to a typical reaction that proceeds to completion overnight at room ...
The magnitude of the equilibrium constant depends on the Gibbs free energy change for the reaction. [2] So, when the free energy change is large (more than about 30 kJ mol −1 ), the equilibrium constant is large (log K > 3) and the concentrations of the reactants at equilibrium are very small.
Biological processes are made of many chemical reactions or other events that are involved in the persistence and transformation of life forms. [1] Regulation of biological processes occurs when any process is modulated in its frequency, rate or extent.
In chemistry, the common-ion effect refers to the decrease in solubility of an ionic precipitate by the addition to the solution of a soluble compound with an ion in common with the precipitate. [1] This behaviour is a consequence of Le Chatelier's principle for the equilibrium reaction of the ionic association / dissociation .