Changing the concentration of a reaction intermediate can have varying effects on the overall rate of a chemical reaction, depending on the specific reaction and its mechanism. In general, increasing the concentration of a reaction intermediate may increase the rate of the reaction, while decreasing the concentration may decrease the rate. However, the actual effect depends on the role of the intermediate in the reaction mechanism and the rate-determining step.A reaction intermediate is a species that is formed and consumed during the course of a reaction but does not appear in the overall balanced equation. It is typically involved in one or more elementary steps of the reaction mechanism.If the reaction intermediate is involved in the rate-determining step the slowest step in the reaction mechanism , then changing its concentration can have a significant impact on the overall reaction rate. In this case, increasing the concentration of the intermediate would likely increase the reaction rate, while decreasing its concentration would likely decrease the rate.However, if the reaction intermediate is not involved in the rate-determining step, then changing its concentration may have little to no effect on the overall reaction rate. This is because the rate-determining step is the bottleneck of the reaction, and any changes in the concentration of intermediates involved in other steps may not significantly impact the overall rate.In summary, the effect of changing the concentration of a reaction intermediate on the overall rate of a chemical reaction depends on the specific reaction mechanism and the role of the intermediate in the rate-determining step.