Question

Under what conditions a bimolecular reaction may be kinetically of first order?

• A. When both reactants have same concentration
• B. When one of the reacting species is in large excess
• C. When the reaction is at equilibrium
• D. When the activation energy of reaction is less

Answer 1

Answer: (B)

When one of the reacting species is in large excess

The pseudo unimolecular reaction is the type of reaction when one reactant is taken in the excess amount that's why it's concentration remains constant even after taking part in the reaction, so we can assume the negligible change in such type of reactants and determine the order from only $1$ reactant.

So the correct option is [B].