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How does a catalyst increase the rate of a chemical reaction?
ABy raising the activation energy of the reaction
BBy increasing the equilibrium constant value
CBy making a non-spontaneous reaction spontaneous
DBy providing an alternate path of lower activation energy
Answer & Solution
Correct answer: D. By providing an alternate path of lower activation energy
1. A catalyst forms a temporary intermediate complex with the reactants.
2. This gives an alternate pathway with a lower activation energy barrier.
3. A lower $E_a$ means a faster rate by the Arrhenius relation.
4. A catalyst does not change $\Delta G$ or the equilibrium constant, ruling out B and C.
_Source: NCERT Class 12 Chemistry Ch 3 "Chemical Kinetics", p.21_
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