I’ve heard many conflicting points on this single question alone. Even the usually reliable sources I run to are pretty ambiguous on the matter. So now I’m here, after 1 and a half weeks of confusion.
As I understand it, there is usually a faster elementary step and a slower elementary step. The slower one is called the “rate-determining step.” My intuition tells me that the actual overall reaction rate (the reaction rate for the whole process) should be higher than the RDS, since the faster step, although it may be magnitudes faster, still takes up time. Thus, it is only the lower limit of the overall reaction rate.
However, I’ve heard plenty of times that the RDS is the overall rate, and when I ask why, the answer is always the same analogy of the motorway with two toll booths. I get the analogy, but I’m not exactly sure if it’s a complete analogy to how a reaction works. No reaction is instantaneous, and this should show especially if the fast step isn’t much faster than the slow step. Yet, I still hear this all over the place, and this wouldn’t be the first time I was wrong about chemistry.