How does adding a positive catalyst affect a chemical reaction?
Answer and explanation
Correct answer: C. It lowers the activation energy by providing an alternative pathway
- Step 1: Recall the function of a catalyst in chemical kinetics.
- Step 2: A catalyst accelerates the rate of forward and reverse reactions equally by offering an alternative mechanism with a lower activation energy (). It does not alter , , or the equilibrium constant .
Answer
It lowers the activation energy by providing an alternative pathway.
Why not the others: Catalysts do not alter , change reaction enthalpy , or modify the thermodynamic equilibrium yield.
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