`Cl_(2)(g)rarr2Cl(g)`, In this process value of `Delta H` will be -

Options

A. Positive
B. Negative
C. Zero
D. Nothing can be predicted

Answer

To determine the value of ΔH for the reaction \( \text{Cl}_2(g) \rightarrow 2\text{Cl}(g) \), we need to analyze the process in terms of bond energies and whether energy is absorbed or released.

### Step-by-Step Solution:

1. **Identify the Reaction**: The reaction given is \( \text{Cl}_2(g) \rightarrow 2\text{Cl}(g) \). This indicates that one molecule of chlorine gas (Cl2) dissociates into two chlorine atoms (Cl).

2. **Understand Bond Energy**: In the diatomic chlorine molecule (Cl2), there is a strong Cl-Cl bond. To break this bond and form two separate chlorine atoms, energy must be supplied to overcome the bond energy.

3. **Determine Energy Change (ΔH)**:
- When a bond is broken, energy is absorbed. Therefore, the process of breaking the Cl-Cl bond requires energy input.
- Since energy is absorbed in this reaction, the change in enthalpy (ΔH) for the reaction will be positive.

4. **Conclusion**: Based on the analysis, since energy is absorbed to break the bond in Cl2, the value of ΔH for the reaction \( \text{Cl}_2(g) \rightarrow 2\text{Cl}(g) \) is positive.

### Final Answer:
The value of ΔH will be positive.