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Chemical Kinetics and Mass Action in Coexisting Phases.

ABSTRACT: The kinetics of chemical reactions are determined by the law of mass action, which has been successfully applied to homogeneous, dilute mixtures. At nondilute conditions, interactions among the components can give rise to coexisting phases, which can significantly alter the kinetics of chemical reactions. Here, we derive a theory for chemical reactions in coexisting phases at phase equilibrium. We show that phase equilibrium couples the rates of chemical reactions of components with their diffusive exchanges between the phases. Strikingly, the chemical relaxation kinetics can be represented as a flow along the phase equilibrium line in the phase diagram. A key finding of our theory is that differences in reaction rates between coexisting phases stem solely from phase-dependent reaction rate coefficients. Our theory is key to interpreting how concentration levels of reactive components in condensed phases control chemical reaction rates in synthetic and biological systems.

SUBMITTER: Bauermann J

PROVIDER: S-EPMC9620980 | biostudies-literature | 2022 Oct

REPOSITORIES: biostudies-literature

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Chemical Kinetics and Mass Action in Coexisting Phases.

Bauermann Jonathan J Laha Sudarshana S McCall Patrick M PM Jülicher Frank F Weber Christoph A CA

Journal of the American Chemical Society 20221014 42

The kinetics of chemical reactions are determined by the law of mass action, which has been successfully applied to homogeneous, dilute mixtures. At nondilute conditions, interactions among the components can give rise to coexisting phases, which can significantly alter the kinetics of chemical reactions. Here, we derive a theory for chemical reactions in coexisting phases at phase equilibrium. We show that phase equilibrium couples the rates of chemical reactions of components with their diffus ...[more]

PMID: 36241174

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