Question

What do you mean by pseudo unimolecular reaction?

Answer 1

Pseudo Unimolecular Reaction. Thereactions having molecularity but order of reaction is one are calledpseudo unimolecular reactions. Thus order of reaction is one butmolecularity of reaction is two.

Answer 2

Pseudo Unimolecular Reaction are reactions having same molecularity but different reaction order are called pseudo unimolecular reactions. They have one reactant in excess and however and whatever process the reaction goes through the reactants concentration remains same all over and throughout.

it looks like a second order reaction but actually is a first order reaction.