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प्रश्न
Define catalyst.
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उत्तर
A catalyst is a substance that either increases or decreases the rate of a chemical reaction without itself undergoing any chemical change during the reaction.
संबंधित प्रश्न
Complete and balance the following chemical equations
Na + H2 O →
MULTIPLE CHOICE QUESTIONS
Tick the most appropriate answer.
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- evaporation
- distillation
- fractional distillation
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Fe + H2O → Fe3O4 + H2
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Name: A brown gas
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Zinc carbonate to zinc oxide
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\[\ce{Fe++->Fe+++}\]
Higher order Thinking question
A very hot glass on putting in cold water cracks. What does this change indicate?
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Write a note on the catalyst.
Why is spoiling food a chemical change?
