Which of the following statements best describes how a catalyst works
Correct answer: C. A catalyst lowers the activation energy barrier for the reaction by providing a different reaction mechanism.
- A. A catalyst changes the potential energies of the reactants and products
- B. A catalyst decreases the temperature of the reaction which leads to a faster rate
- C. A catalyst lowers the activation energy barrier for the reaction by providing a different reaction mechanism.
- D. A catalyst raises the activation energy for the reaction which produces a faster rate
Explanation
Catalysts function by providing an alternate reaction mechanism that has a lower activation energy.Note that a catalyst decreases the activation energy for both the forward and the backward reactions hence, accelerates both the forward and the backward reactions.
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About Activation Energy and Activated Complex
Activation energy is the minimum energy reactant particles need to form the activated complex, or transition state, during a reaction. Energy profile diagrams show the forward and reverse activation energies, while catalysts provide an alternative pathway with lower activation energy without changing the reaction enthalpy.
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