Define exothermic reactions. Give two examples of each. - Vidyadip

Question

Define exothermic reactions. Give two examples of each.

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Answer

Exothermic reactions: The chemical reaction in which heat is given out is called exothermic reactions. It causes rise in temperature. .
e.g. $(i)$ When carbon bums in oxygen to form carbon dioxide, a lot of heat is produced.
$C + O_2 \rightarrow CO_2 +$ heat.
When water is added to quicklime a lot of heat is produced which boils the water.
$\ce{CaO} + \ce{H_2O} \rightarrow \ce{Ca(OH)_2} +$ Heat.

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