What do you understand by exothermic reaction and endothermic reaction? Give one example of each type.
(N/A) Exothermic reactions: Reactions which evolve heat are known as exothermic reactions. Evolution of heat can be shown using a '$+$' sign or by a $\Delta H$ with a '$-$' sign along with the product.
Example: $C_{(s)} + O_{2(g)} \longrightarrow CO_{2(g)} + 393.5 \ kJ$
Endothermic reactions: Reactions which absorb heat are called endothermic reactions. Absorbed heat can be shown as a '$-$' sign or in terms of $\Delta H$ with a '$+$' sign.
Example: $C_{(s)} + H_{2}O_{(g)} \longrightarrow CO_{(g)} + H_{2(g)} - 131.4 \ kJ$
Example: $C_{(s)} + O_{2(g)} \longrightarrow CO_{2(g)} + 393.5 \ kJ$
Endothermic reactions: Reactions which absorb heat are called endothermic reactions. Absorbed heat can be shown as a '$-$' sign or in terms of $\Delta H$ with a '$+$' sign.
Example: $C_{(s)} + H_{2}O_{(g)} \longrightarrow CO_{(g)} + H_{2(g)} - 131.4 \ kJ$
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