Which of the following explains, in terms of collision theory, why this reaction occurs in more than one step? A. a low \( \mathrm{C}_{5} \mathrm{H}_{12}(8) \) concentration B. low temperature of reactant mixture C. low probability of multi-particle collision D. particles collide with insufficient kinetic energy

To determine which option explains why a reaction occurs in more than one step in terms of collision theory, let's analyze each option: A. **A low \( \mathrm{C}_{5} \mathrm{H}_{12}(8) \) concentration**: A low concentration of reactants can lead to fewer collisions, but it does not inherently explain why a reaction would occur in multiple steps. It may slow down the reaction but does not dictate the mechanism. B. **Low temperature of reactant mixture**: Low temperatures generally result in lower kinetic energy of the particles, which can lead to fewer effective collisions. However, this does not directly explain the multi-step nature of a reaction. C. **Low probability of multi-particle collision**: This option suggests that the likelihood of simultaneous collisions between multiple particles is low. In many reactions, especially those involving complex molecules, it is more probable for reactions to occur in a series of simpler steps rather than a single multi-particle collision. This aligns well with the concept of reaction mechanisms, where intermediate species are formed. D. **Particles collide with insufficient kinetic energy**: While insufficient kinetic energy can prevent a reaction from occurring, it does not explain why a reaction would take place in multiple steps. It simply indicates that the reaction may not proceed at all. Based on this analysis, the best explanation in terms of collision theory for why a reaction occurs in more than one step is: **C. low probability of multi-particle collision**.