Detailed Instructions: In this task, you are given a multiple-choice question about healthcare. Answer the question based on your information and classify your answers into '1', '2', '3', and '4'.
Problem:Question: The molecularity of an elementary reaction corresponds:
Options: <1> At the initial concentration of reagent. <2> To the number of molecules that are found to react. <3> To the number of collisions of the reactants per unit of time. <4> At the final concentration of the product. <5> To the reaction between the reaction rate and the reagent concentration.
Solution:
2