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 a given \(\Delta H = -26.4\) Kcal, we need to analyze the thermodynamic implications of the reaction.

### Step-by-Step Solution:

1. **Understand the Reaction**: The reaction involves solid carbon (C) reacting with half a mole of gaseous oxygen (\(O_2\)) to form carbon monoxide (CO).

2. **Identify the Sign of \(\Delta H\)**: The value of \(\Delta H\) is given as \(-26.4\) 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 an exothermic reaction, the products have lower energy than the reactants, and energy is released to the surroundings.

4. **Analyze the Product (CO)**: The question asks whether CO is an endothermic or exothermic compound. Since the formation of CO from its elements (C and \(O_2\)) is exothermic (as indicated by the negative \(\Delta H\)), we conclude that CO is an exothermic compound.

5. **Conclusion**: Based on the information provided, we can conclude that CO is an exothermic compound.

### Final Answer:
CO is an exothermic compound.

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