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  2. Iodine clock reaction - Wikipedia

    en.wikipedia.org/wiki/Iodine_clock_reaction

    The iodine clock reaction is a classical chemical clock demonstration experiment to display chemical kinetics in action; it was discovered by Hans Heinrich Landolt in 1886. [1] The iodine clock reaction exists in several variations, which each involve iodine species ( iodide ion, free iodine, or iodate ion) and redox reagents in the presence of ...

  3. Chemical clock - Wikipedia

    en.wikipedia.org/wiki/Chemical_clock

    In an iodine clock reaction, colour changes after a time delay.. A chemical clock (or clock reaction) is a complex mixture of reacting chemical compounds in which the onset of an observable property (discoloration or coloration) occurs after a predictable induction time due to the presence of clock species at a detectable amount. [1]

  4. Reaction mechanism - Wikipedia

    en.wikipedia.org/wiki/Reaction_mechanism

    In chemistry, a reaction mechanism is the step by step sequence of elementary reactions by which overall chemical reaction occurs. [1] A chemical mechanism is a theoretical conjecture that tries to describe in detail what takes place at each stage of an overall chemical reaction. The detailed steps of a reaction are not observable in most cases.

  5. Reaction intermediate - Wikipedia

    en.wikipedia.org/wiki/Reaction_intermediate

    In chemistry, a reaction intermediate, or intermediate, is a molecular entity arising within the sequence of a stepwise chemical reaction. It is formed as the reaction product of an elementary step, from the reactants and/or preceding intermediates, but is consumed in a later step. It does not appear in the chemical equation for the overall ...

  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. Delay differential equation - Wikipedia

    en.wikipedia.org/wiki/Delay_differential_equation

    DDEs are also called time-delay systems, systems with aftereffect or dead-time, hereditary systems, equations with deviating argument, or differential-difference equations. They belong to the class of systems with the functional state , i.e. partial differential equations (PDEs) which are infinite dimensional, as opposed to ordinary ...

  8. Dynamic kinetic resolution in asymmetric synthesis - Wikipedia

    en.wikipedia.org/wiki/Dynamic_Kinetic_Resolution...

    Dynamic kinetic resolution of 1,4 conjugate reduction. The rate-limiting step is the copper complex interaction with the double bond and the transfer of hydrogen. 1,4 conjugate reduction to cyclic enones. Copper proved to be an excellent metal in this reaction due to its ability to complex with the oxygen when the hydrogen was added.

  9. Chain propagation - Wikipedia

    en.wikipedia.org/wiki/Chain_propagation

    In chemistry, chain propagation (sometimes just referred to as propagation) is a process in which a reactive intermediate is continuously regenerated during the course of a chemical chain reaction. For example, in the chlorination of methane , there is a two-step propagation cycle involving as chain carriers a chlorine atom and a methyl radical ...