A student monitors the forward and reverse rates of the reaction A ⇌ B
CHEMISTRY · Single correct · A Level · Chemistry · Chemical equilibria (Le Chatelier’s principle and Kc) · Chemical equilibria (Le Chatelier’s principle and Kc)
Problem
A student monitors the forward and reverse rates of the reaction A ⇌ B. The two rate curves intersect at 45 s and remain superimposed for all later times. Which of the following best explains what is happening in the reaction mixture after 45 s?
(a) The reaction has gone to completion, so neither the forward nor reverse process occurs.
(b) The forward and reverse rates are equal because the concentrations of A and B have become equal.
(c) Both the forward and reverse reactions continue at equal rates, so the macroscopic concentrations remain constant.
(d) Only the reverse reaction proceeds after 45\,s because products are favored.