According to the following reaction `C(S)+1//2O_(2)(g)rarr CO(g), Delta H=-26.4` Kcal

Options

A. CO is an endothermic compound
B. CO is an exothermic compound
C. The reaction is endothermic
D. None of the above

Answer

To solve the question regarding the reaction \( C(S) + \frac{1}{2}O_2(g) \rightarrow CO(g) \) with \(\Delta H = -26.4 \, \text{kcal}\), we will analyze the thermodynamic implications of the given reaction.

### Step-by-Step Solution:

1. **Identify the Reaction**: The reaction given is:
\[ C(S) + \frac{1}{2}O_2(g) \rightarrow CO(g) \]
Here, solid carbon reacts with half a mole of gaseous oxygen to produce carbon monoxide gas.

2. **Understand the Significance of \(\Delta H\)**: The enthalpy change (\(\Delta H\)) for the reaction is given as \(-26.4 \, \text{kcal}\). The negative sign indicates that the reaction releases energy.

3. **Determine the Nature of the Reaction**: Since the reaction releases energy, it is classified as an **exothermic reaction**. In exothermic reactions, the products have lower energy than the reactants, and energy is released in the form of heat.

4. **Conclusion**: Based on the information that the reaction is exothermic due to the negative \(\Delta H\), we can conclude that carbon monoxide (CO) is an exothermic compound.

5. **Select the Correct Option**: If the options provided include a statement indicating that CO is an exothermic compound, that would be the correct answer. According to the video transcript, option B is identified as the correct choice.

### Final Answer:
The correct option is B, indicating that CO is an exothermic compound.

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