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

Question

Define endothermic reactions. Give two examples of each.

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Answer

Endothermic reaction: A chemical reaction in which heat is absorbed is called endothermic reaction. It causes fall in temperature.
e.g. $(i)$ When nitrogen and oxygen together are heated to a temperature of about $3000^\circ C,$ nitric oxide gas is formed.
$N_2 + O_2 +$ heat $\rightarrow \ce{2NO(g)}$
$(ii)$ Decomposition of calcium carbonate into carbon dioxide and calcium oxide when heated to a $1000^\circ C.$
$\ce{CaCO_3} +$ Heat $\rightarrow \ce{CaO(s)} + \ce{CO_2(g)}$

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