Which of the following reaction is not endothermic in nature?

Options

A. breaking in bonds
B. digestion of food
C. combustion of Carbon
D. evaporation of water

Answer

To determine which of the given reactions is not endothermic in nature, we first need to understand the definitions of endothermic and exothermic reactions.

### Step-by-Step Solution:

1. **Define Endothermic and Exothermic Reactions**:
- Endothermic reactions are those that absorb heat from the surroundings. This means that energy is required for the reaction to occur, often resulting in a temperature drop in the environment.
- Exothermic reactions, on the other hand, release heat into the surroundings. This means that energy is produced during the reaction, often resulting in a temperature increase in the environment.

2. **Analyze the Reactions**:
- We need to look at the reactions provided in the question (though they are not listed here, we can assume typical examples).
- For example, common endothermic reactions include photosynthesis, the melting of ice, and the thermal decomposition of calcium carbonate.
- Common exothermic reactions include combustion (like burning wood or fossil fuels), respiration, and the reaction of acids with bases.

3. **Identify the Non-Endothermic Reaction**:
- From the list of reactions, we need to identify which one does not absorb heat and instead releases heat.
- For instance, if one of the reactions is combustion (like burning methane), this would be an exothermic reaction and thus not endothermic.

4. **Conclusion**:
- After analyzing the reactions, we can conclude which reaction is not endothermic.

### Final Answer:
- The reaction that is not endothermic in nature is the exothermic reaction (for example, combustion).