When the temperature of a gas-phase reaction mixture is raised from 300 K to 320 K
CHEMISTRY · Single correct · AP · Chemistry · Kinetics · Kinetics
Problem
When the temperature of a gas-phase reaction mixture is raised from 300 K to 320 K, the observed reaction rate approximately doubles. Which of the following best explains this observation?
(a) The average molecular speed increases, so collisions occur more frequently, causing the reaction rate to double.
(b) A greater fraction of molecular collisions possesses energy equal to or exceeding the activation energy.
(c) The activation energy of the reaction decreases as temperature rises, so reactants need less energy to react.
(d) The higher temperature improves molecular orientation, so a larger fraction of collisions are effective.