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  2. Activation energy - Wikipedia

    en.wikipedia.org/wiki/Activation_energy

    Activation energy can be thought of as the magnitude of the potential barrier (sometimes called the energy barrier) separating minima of the potential energy surface pertaining to the initial and final thermodynamic state. For a chemical reaction to proceed at a reasonable rate, the temperature of the system should be high enough such that ...

  3. Activation - Wikipedia

    en.wikipedia.org/wiki/Activation

    The energy of activation [1] specifies the amount of free energy the reactants must possess (in addition to their rest energy) in order to initiate their conversion into corresponding products—that is, in order to reach the transition state for the reaction. The energy needed for activation can be quite small, and often it is provided by the ...

  4. Activated complex - Wikipedia

    en.wikipedia.org/wiki/Activated_complex

    The activation energy is the minimum amount of energy to initiate a chemical reaction and form the activated complex. [6] The energy serves as a threshold that reactant molecules must surpass to overcome the energy barrier and transition into the activated complex.

  5. Chemical reaction - Wikipedia

    en.wikipedia.org/wiki/Chemical_reaction

    Higher activation energy implies that the reactants need more energy to start than a reaction with lower activation energy. Temperature, which hastens reactions if raised, since higher temperature increases the energy of the molecules, creating more collisions per unit of time, The presence or absence of a catalyst.

  6. Transition state theory - Wikipedia

    en.wikipedia.org/wiki/Transition_state_theory

    The free energy of activation, ΔG ‡, is defined in transition state theory to be the energy such that ‡ = ⁡ ‡ ′ holds. The parameters ΔH ‡ and ΔS ‡ can then be inferred by determining ΔG ‡ = ΔH ‡ – TΔS ‡ at different temperatures.

  7. Collision theory - Wikipedia

    en.wikipedia.org/wiki/Collision_theory

    The successful collisions must have enough energy, also known as activation energy, at the moment of impact to break the pre-existing bonds and form all new bonds. This results in the products of the reaction. The activation energy is often predicted using the Transition state theory. Increasing the concentration of the reactant brings about ...

  8. Energy profile (chemistry) - Wikipedia

    en.wikipedia.org/wiki/Energy_profile_(chemistry)

    For any reaction to proceed, the starting material must have enough energy to cross over an energy barrier. This energy barrier is known as activation energy (∆G ≠) and the rate of reaction is dependent on the height of this barrier. A low energy barrier corresponds to a fast reaction and high energy barrier corresponds to a slow reaction.

  9. Transition state - Wikipedia

    en.wikipedia.org/wiki/Transition_state

    The concept of a transition state has been important in many theories of the rates at which chemical reactions occur. This started with the transition state theory (also referred to as the activated complex theory), which was first developed around 1935 by Eyring, Evans and Polanyi, and introduced basic concepts in chemical kinetics that are still used today.