Slow Step

[Joshua Eidam 2A]

Sorry if this is the wrong section to be posting this question but I am confused as to what the slow step is in a reaction and how to identify it? Why is it called the slow step?

[Katie_Dinh_1D]

The rate of the overall reaction is dictated by the rate of the slow step in a reaction mechanism. A good analogy would be a group of people walking, but the pace of the group is determined by the slowest member. In order to identify the slow step in a proposed mechanism, its rate law would have to match the experimentally determined rate law of the overall reaction. Hope this helps!

[Alex Mele 2A]

To add on to the previous comment, you can look at the slow step of the reaction to determine the rate law but still have to eliminate intermediates from the final rate law. You can do this by looking at another step of the reaction to substitute out for an equal concentration.

[Alan Huang 1E]

The slow step of a reaction is, well, the slowest part of a reaction. As most chemical reactions don't occur in one motion, there are several stages that a reaction goes through. The slow step is the step that takes the longest time in a reaction. It is the rate determining step and can be compared to the neck of a funnel.

[LarisaAssadourian2K]

This is my best analogy for the significance of the slow step. Let's say you are climbing multiple mountains. There is one very big one and two very small ones. Since climbing the biggest mountain is going to take up most of your time, you could make the best estimate of the time it took to climb the mountains based on that one. The largest mountain is the one that had the greatest effect on the amount of time it took to climb all of them. That is why the slow reaction (biggest mountain) is the rate-determining step.

[Joel Meza 3I]

The slow step doesn't occur as fast as the other elementary steps. Thus, the rate of the reaction as a whole essentially depends on the rate of this slow step. The step before the slow step will be considered in equilibrium because there will be a build-up of products and some of the products will go back to the reactants in a reverse reaction.

[Valerie Tran 2B]

To identify the slow step and the reaction mechanisms, you need to consider:
1) the sum of elementary steps = overall reaction
2) the mechanisms must agree with the experimentally determined rate law. Whichever elementary step has a rate law that matches the overall reaction's rate law is the slow step.

The slow step determines the rate

[Danielle DIS2L]

The slowest step is the one that takes the most time. Based on what is said above regarding mountains, you can say that climbing the biggest mountain would take more time which would be the slowest step. In chemistry, the slowest step would be the one that has the steepest slope.

[Linette Choi 3L]

The slow step is the one that determines the rate of the overall mechanism. It should state on the question which reactions are slow or fast.

[JoshMoore2B]

Sorry if this is the wrong section to be posting this question but I am confused as to what the slow step is in a reaction and how to identify it? Why is it called the slow step?

The slow step in a reaction is called a slow step because it is the step in which the reactants take longest to become products. This step, being the slowest, is the sole determinant in the rate of a reaction.

The best way to identify it is to compare the rate laws of each of the intermediate steps with the overall rate law. The slow step's law and the overall law of the reaction will be the same.

[Kelly Tran 1J]

The slow step of a mechanism is the rate limiting step; it determines the rate of the overall reaction. You can identify the slow step from a mechanism by determining whether the rate law of that step matches the rate law of the overall reaction.

[arisawaters2D]

Just to clarify, so the overall reaction rate doesn't include the faster step?

[Jack_Pearce_2H]

So basically the slow step of a reaction is the step that determines the rate of the reaction because it is the "slowest" and thus determines how fast the reaction is. Kind of like the limiting reactant. Also you can identify it by seeing which rate law is closest to the primary rate law in the problem.

[Edgar Velazquez 2K]

The slow step is exactly what it sounds like, the slowest step in the reaction. The rate of the reaction can only be as fast as it's slowest step, so the slow step is what the rate is based on.

[Joshua Chung 2D]

The slowest step of a reaction is the one that determines the rate of the entire reaction. You can identify it by comparing the individual steps' rate laws to the overall rate law.