Same chapter3 marksDifficulty: Medium
What is a catalyst? Give one example with the reaction it catalyses.
Chemical Changes and Reactions
3 marksDifficulty: Medium
Distinguish between an exothermic and an endothermic reaction, with one example of each.
Original Khojo Papers practice question — not from a past board paper.
Answer
An exothermic reaction gives out heat to the surroundings, so the temperature rises; the burning of magnesium is an example. An endothermic reaction absorbs heat, so the temperature falls; the decomposition of calcium carbonate on strong heating is an example.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
Photosynthesis is an endothermic reaction driven by light rather than heat.
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