State the role of activated complex in a reaction and state the relation with energy of activation.

State the role of activated complex in a reaction and state the relation with energy of activation.
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Ans.: When the colliding reactant molecules possess the kinetic energy equal to energy of activation then the configuration of atoms of the species at this state is different from the reactants as well as the products.This state is called activated or transition state and specific configuration of this state is called activated complex.

The reactant molecules do not change directly into products, first they absorb energy equivalent to the energy of activation and form an activated complex. The activated complex formed has a very short life spam and splits into the products. The activated complex is at the top of the energy barrier graph and possess the highest energy. In this activated complex, all the bonds are in the transition state.

Low energy activation barrier means the activated complex is readily formed and it is fast reaction.

High energy of activation barrier means the activated complex is difficult to form and it is a slow reaction.

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