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  2. Reaction rate - Wikipedia

    en.wikipedia.org/wiki/Reaction_rate

    Iron rusting has a low reaction rate. This process is slow. Wood combustion has a high reaction rate. This process is fast. The reaction rate or rate of reaction is the speed at which a chemical reaction takes place, defined as proportional to the increase in the concentration of a product per unit time and to the decrease in the concentration of a reactant per unit time. [1]

  3. Rate-determining step - Wikipedia

    en.wikipedia.org/wiki/Rate-determining_step

    In chemical kinetics, the overall rate of a reaction is often approximately determined by the slowest step, known as the rate-determining step (RDS or RD-step [1] or r/d step [2] [3]) or rate-limiting step. For a given reaction mechanism, the prediction of the corresponding rate equation (for comparison with the experimental rate law) is often ...

  4. Reaction rate constant - Wikipedia

    en.wikipedia.org/wiki/Reaction_rate_constant

    where A and B are reactants C is a product a, b, and c are stoichiometric coefficients,. the reaction rate is often found to have the form: = [] [] Here ⁠ ⁠ is the reaction rate constant that depends on temperature, and [A] and [B] are the molar concentrations of substances A and B in moles per unit volume of solution, assuming the reaction is taking place throughout the volume of the ...

  5. Diffusion-controlled reaction - Wikipedia

    en.wikipedia.org/wiki/Diffusion-controlled_reaction

    The process of chemical reaction can be considered as involving the diffusion of reactants until they encounter each other in the right stoichiometry and form an activated complex which can form the product species. The observed rate of chemical reactions is, generally speaking, the rate of the slowest or "rate determining" step.

  6. Chemical kinetics - Wikipedia

    en.wikipedia.org/wiki/Chemical_kinetics

    Chemical kinetics, also known as reaction kinetics, is the branch of physical chemistry that is concerned with understanding the rates of chemical reactions. It is different from chemical thermodynamics , which deals with the direction in which a reaction occurs but in itself tells nothing about its rate.

  7. Enzyme kinetics - Wikipedia

    en.wikipedia.org/wiki/Enzyme_kinetics

    The substrate concentration midway between these two limiting cases is denoted by K M. Thus, K M is the substrate concentration at which the reaction velocity is half of the maximum velocity. [2] The two important properties of enzyme kinetics are how easily the enzyme can be saturated with a substrate, and the maximum rate it can achieve.

  8. Reactions on surfaces - Wikipedia

    en.wikipedia.org/wiki/Reactions_on_surfaces

    The reaction order is 1 with respect to B and −1 with respect to A. Reactant A inhibits the reaction at all concentrations. The following reactions follow a Langmuir–Hinshelwood mechanism: [4] 2 CO + O 2 → 2 CO 2 on a platinum catalyst. CO + 2H 2 → CH 3 OH on a ZnO catalyst. C 2 H 4 + H 2 → C 2 H 6 on a copper catalyst. N 2 O + H 2 ...

  9. Transition state theory - Wikipedia

    en.wikipedia.org/wiki/Transition_state_theory

    In chemistry, transition state theory (TST) explains the reaction rates of elementary chemical reactions. The theory assumes a special type of chemical equilibrium (quasi-equilibrium) between reactants and activated transition state complexes. [1] TST is used primarily to understand qualitatively how chemical reactions take place.