a student proposes the following step of a mechanism. why would an expert question this mechanism step? 3a +…

a student proposes the following step of a mechanism. why would an expert question this mechanism step? 3a + b → 2c\na the number of reactants and products must be the same.\nb the number of products must always exceed the reactants.\nc this would require 4 molecules to collide and react simultaneously.\nd this step should be reversible.\ne an expert would not question this step.
Answer
Brief Explanations:
In chemical reaction mechanisms, the probability of four molecules (3A + B) colliding simultaneously is extremely low. This makes such a proposed elementary step suspect.
Answer:
C. This would require 4 molecules to collide and react simultaneously.