Rate Determining Step
Recall: The rate determining step is the slowest step in a reaction mechanism
You and a group of friends decide to join in a team marathon. All of you will run the race at once and the winning team will be the first team in which all the members cross the finish line. The speed of a team is only determined by the slowest runner. Similarly, in reaction mechanisms, the rate of reaction is determined by the rate of the slowest reaction, or the rate determining step. The speed at which the faster reactions occur is negligible when compared to the overall rate of reaction.
1. Which team would win, a team of average-speed runners, or a team of very fast runners, and a couple slow runners?
2. Which is the rate determining step?
X+Y → Z Rate of Reaction 1.5 hours
Z+A → W Rate of Reaction 4680 seconds
W+A→ B Rate of Reaction 87 minutes
3. Why is it useful to know the rate determining step?