Question
What is called an exothermic chemical reaction? Give examples.
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Answer
- Chemical reaction in which heat is released during the formation of product is called an exothermic reaction.
- Examples:
- $(1)$ Burning of natural gas:
- $\mathrm{CH}_4(\mathrm{~g})+2 \mathrm{O}_2(\mathrm{~g}) \rightarrow \mathrm{CO}_2(\mathrm{~g})+2 \mathrm{H}_2 \mathrm{O}(\mathrm{~g})$
- $(2)$ Burning of coal:
- $\mathrm{C}(\mathrm{~s})+\mathrm{O}_2(\mathrm{~g}) \rightarrow \mathrm{CO}_2(\mathrm{~g})+\text { Heat }$
- $(3)$ Formation of compost manure by decomposition of vegetable matter is also an example of an exothermic reaction.
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