CHM 1311 Lecture Notes - Lecture 8: Elementary Reaction, Reaction Mechanism, Molecularity

• School: University of Ottawa
• Department: Chemistry
• Course: CHM 1311
• Professor: Matthew Lafreniere

Document Summary

Reaction mechanism: the exact molecular pathway that starting materials follow on their way to becoming products. Elementary reaction: the individual steps of a reaction mechanism. The overall reaction mechanisms describes the formation of products and the elimination of reagents. Elementary reactions describe the individual steps of the overall reaction mechanism. Some reaction mechanisms form intermediates, which are species that are not part of the overall stoichiometry but are produces in the early part of a reaction and consumed in a later part of the reaction. If we use no2 as an example, we can describe the overall reaction, the elementary steps in a reaction reaction, and the reaction intermediates: Notably, there is a wide variety of possible elementary steps to form the same overall reaction: The rate-determining steps (rds): the slowest step in a reaction mechanism. The rds dictates the rate of the overall chemical reaction because no reaction can proceed faster than its slowest step.