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प्रश्न
What does one mean by exothermic reaction? Give example.
उत्तर १
Reactions in which heat is released along with the formation of products are called exothermic chemical reactions.
Example: \[\ce{C(s) + O2(g) -> CO2(g) + Heat}\]
\[\ce{2H2(g) + O2(g) -> 2H2O(l) + Heat}\]
उत्तर २
A reaction in which heat is released is called an exothermic reaction. Burning of fuel is an example of exothermic reaction. When methane is burned, it gives heat along with carbon dioxide and water.
\[\ce{CH4(g) + 2O2(g) -> CO2(g) + 2H2O(l) + Heat}\]
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