Question

Classify the following reaction into exothermic and endothermic reactions-

Reaction between glucose and oxygen.

Answer 1

1. Exothermic reactions: The reactions in which heat (energy) is evolved are called exothermic reactions.
2. Endothermic reactions: The reactions in which heat (energy) is absorbed during a reaction are called endothermic reactions.
3. Reaction between Glucose and oxygen:

• Glucose (${\mathrm{C}}_6{\mathrm{H}}_{12}{\mathrm{O}}_6$) combines with oxygen (${\mathrm{O}}_2$) in our body to produce carbon dioxide (${\mathrm{CO}}_2$) and water (${\mathrm{H}}_2\mathrm{O}$) with the release of a huge amount of energy.

$$\begin{gathered} {\mathrm{C}}_6{\mathrm{H}}_{12}{\mathrm{O}}_6\left(\mathrm{s}\right)+6{\mathrm{O}}_2\left(\mathrm{g}\right)\to 6{\mathrm{CO}}_2\left(\mathrm{g}\right)+6{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right)+\mathrm{Heat} \\ \mathrm{Glucose}\mathrm{Oxygen}\mathrm{Carbon}\mathrm{Water} \\ \mathrm{dioxide} \end{gathered}$$

4. The heat is evolved here. Hence, the reaction between glucose and oxygen is an exothermic reaction.