Another name for the activated complex is
a. energy barrier
b. transition state
c. rate limiter
d. collision group

                   Another name for the activated complex is Transition State.

                     According to Collision Theory for a chemical reaction to occur the reactants must collide with proper orientation and required energy. In this way the old bonds are broken and new bonds are formed. The mid point of highest energy at which both bond formation and breakage is taking place is called activation complex, a complex in between reactant and product.

                      The energy of this complex is the minimum amount of energy required for a particular reactants to convert into products and is called as Activation Energy.

                      This activation complex is also termed as Transition State because according to Transition State Theory at transition state the existing bonds tend to increase in length and become weaken while, the new forming bonds tend to decrease in length and start becoming stronger. Hence, the activated complex is in transition between reactants and products.