Question

question 3 (1 point)
consider the following reaction mechanism. changing the concentration of which substance(s) would have the most effect on the rate of the overall reaction?
2a --> b + 2c (slow)
b + c --> d + e (fast)
c + d --> e + f (fast)
a
a and c
b
d
d and e

Explanation:

In a reaction mechanism, the rate - determining step (the slow step) governs the overall reaction rate. The rate law for the slow step \(2A
ightarrow B + 2C\) is \(rate = k[A]^2\) (assuming it is an elementary reaction). Substances \(B\), \(C\), \(D\), and \(E\) are involved in fast steps. Fast steps have a negligible impact on the overall reaction rate compared to the slow step. Since the rate law of the slow step only depends on the concentration of \(A\), changing the concentration of \(A\) will have the most effect on the rate of the overall reaction.

Answer:

A. A