Which one of the following statements describes the effect that adding a catalyst will have on the energy profile diagram for an exothermic reaction?
A - VCE - SSCE Chemistry - Question 24 - 2021 - Paper 1
Question 24
Which one of the following statements describes the effect that adding a catalyst will have on the energy profile diagram for an exothermic reaction?
A. The energy ... show full transcript
Worked Solution & Example Answer:Which one of the following statements describes the effect that adding a catalyst will have on the energy profile diagram for an exothermic reaction?
A - VCE - SSCE Chemistry - Question 24 - 2021 - Paper 1
Step 1
A. The energy of the products will remain the same.
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Answer
This statement is true. The addition of a catalyst does not affect the energy of the reactants or products; it only lowers the activation energy for the reaction.
Step 2
B. The shape of the energy profile diagram will remain the same.
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Answer
This statement is also true. Adding a catalyst modifies the activation energy barrier but does not change the overall energy profile shape for the exothermic reaction.
Step 3
C. The peak of the energy profile will move to the left as the reaction rate increases.
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This statement is misleading. While a catalyst increases the reaction rate by lowering the activation energy, the peak of the energy profile does not physically move; rather, the reaction can proceed more quickly because the energy barrier is lowered.
Step 4
D. The activation energy will be lowered by the same proportion in the forward and reverse reactions.
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This statement is correct. A catalyst lowers the activation energy for both the forward and reverse reactions equally, facilitating both pathways without favoring one over the other.
