CBSE Class 12 · 2001 · All India · Chemical KineticsShort Answer

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

Solution

The activated complex is the unstable, transient arrangement of atoms at the top of the energy barrier, formed momentarily when energised reactant molecules collide; it may break up into products (or revert to reactants).
Relation with activation energy:

E_{a} = E_{activated complex} - E_{reactants (average)}

— the reactants must absorb exactly this much extra energy to form the complex and hence the products.

CBSE Class 12 Board · 2001 · All India · Subjective

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