Addition of a small amount of MnO powder greatly accelerates the decomposition of…
CHEMISTRY · Single correct · A Level · Chemistry · Kinetics · Kinetics
Problem
Addition of a small amount of MnO2 powder greatly accelerates the decomposition of hydrogen peroxide, yet analysis shows that the mass of MnO2 is unchanged after the reaction is complete. Which of the following best explains how MnO2 increases the reaction rate?
(a) MnO2 increases the average kinetic energy of H2O2 molecules, so more collisions exceed the activation‐energy barrier.
(b) MnO2 shifts the reaction equilibrium toward products, in accordance with Le Châtelier’s principle.
(c) MnO2 provides an alternative reaction pathway that has a lower activation energy.
(d) MnO2 supplies additional oxygen atoms that are consumed during the reaction.