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प्रश्न
Define catalyst.
उत्तर
A catalyst is a substance that either increases or decreases the rate of a chemical reaction without itself undergoing any chemical change.
\[\ce{N2 + 3H2 ⇌[Iron (Catalyst) 200 - 900][450°C] 2NH3 + Heat}\]
here iron act as a catalyst and increases the rate of chemical reaction.
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