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Question
Explain the effect of catalyst on reaction rate with an example.
Solution
1. Significant changes in the reaction can be brought out by the addition of a substance called catalyst.
2. A catalyst is substance which alters the rate of a reaction without itself undergoing any permanent chemical change.
3. They may participate in the reaction, but again regenerate and the end of the reaction.
4. In the presence of a catalyst, the energy of activation is lowered and hence, the greater number of molecules can cross the energy barrier and change over to products, thereby increasing the rate of the reaction.
5. For example, the decomposition of potassium chlorate is enhanced by the addition of MnO2.
\[\ce{2KClO3 ->[MnO4][\Delta] 2KCl + 3O2 (MnO2 - Catalyst)}\]
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