Two elementary reactions of separate compounds are characterized at 298 K as follows
CHEMISTRY · Single correct · AP · Chemistry · Thermodynamics and Electrochemistry · Thermodynamics and Electrochemistry
Problem
Two elementary reactions of separate compounds are characterized at 298 K as follows.
• Reaction 1: Ea=25kJmol−1, ΔG∘=−5kJmol−1
• Reaction 2: Ea=95kJmol−1, ΔG∘=−40kJmol−1
Which statement is most consistent with these data?
(a) Reaction 2 is more thermodynamically favorable, but Reaction 1 will occur faster; observing only the product of Reaction 1 would indicate kinetic control.
(b) Because Reaction 2 has the more negative ΔG∘, it will both proceed faster and give the predominant product regardless of temperature.
(c) Increasing the temperature would favor Reaction 1 because its lower activation energy means its rate will rise more sharply than that of Reaction 2.
(d) If only the product of Reaction 2 is formed, the system is said to be under kinetic control because its ΔG∘ is more negative.