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  2. 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 ...

  3. Collision theory - Wikipedia

    en.wikipedia.org/wiki/Collision_theory

    The rate for a bimolecular gas-phase reaction, A + B → product, predicted by collision theory is [6] = = ⁡ ()where: k is the rate constant in units of (number of molecules) −1 ⋅s −1 ⋅m 3.

  4. 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]

  5. Transition state theory - Wikipedia

    en.wikipedia.org/wiki/Transition_state_theory

    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 ...

  6. Rate-determining step - Wikipedia

    en.wikipedia.org/wiki/Rate-determining_step

    As an example, consider the gas-phase reaction NO 2 + CO → NO + CO 2.If this reaction occurred in a single step, its reaction rate (r) would be proportional to the rate of collisions between NO 2 and CO molecules: r = k[NO 2][CO], where k is the reaction rate constant, and square brackets indicate a molar concentration.

  7. Equilibrium constant - Wikipedia

    en.wikipedia.org/wiki/Equilibrium_constant

    Indeed, for ideal-gas reactions K p is independent of pressure. [17] Pressure dependence of the water ionization constant at 25 °C. In general, ionization in aqueous solutions tends to increase with increasing pressure. In a condensed phase, the pressure dependence of the equilibrium constant is associated with the reaction volume. [18] For ...

  8. Activation energy - Wikipedia

    en.wikipedia.org/wiki/Activation_energy

    where A is the pre-exponential factor for the reaction, R is the universal gas constant, T is the absolute temperature (usually in kelvins), and k is the reaction rate coefficient. Even without knowing A, E a can be evaluated from the variation in reaction rate coefficients as a function of temperature (within the validity of the Arrhenius ...

  9. Law of mass action - Wikipedia

    en.wikipedia.org/wiki/Law_of_mass_action

    The affinity constants, k + and k −, of the 1879 paper can now be recognised as rate constants. The equilibrium constant, K, was derived by setting the rates of forward and backward reactions to be equal. This also meant that the chemical affinities for the forward and backward reactions are equal. The resultant expression