Compound `A(C_6H_(12))` does not absorb `H_(2)` in presence of Ni. It forms two monochloro isomers on photochemical chlorination . Its structure can be

Options

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B.
C.
D.

Explanation

To solve the problem regarding compound A (C₆H₁₂), we will analyze the information provided step by step.

### Step 1: Analyze the Molecular Formula
The molecular formula of compound A is C₆H₁₂. This indicates that it is an alkene or a cycloalkane because it has the general formula CₙH₂ₙ for alkenes or CₙH₂ₙ for cycloalkanes. The fact that it does not absorb H₂ in the presence of nickel suggests that it is not an alkene, as alkenes typically undergo hydrogenation.

**Hint:** Remember that alkenes can be hydrogenated, while cycloalkanes cannot.

### Step 2: Determine the Structure of Compound A
Since compound A does not absorb H₂, it is likely a cycloalkane. The only cycloalkane with the formula C₆H₁₂ is cyclohexane (C₆H₁₂).

**Hint:** Consider the properties of cycloalkanes and their saturation levels.

### Step 3: Photochemical Chlorination
The problem states that compound A forms two monochloro isomers upon photochemical chlorination. In the case of cyclohexane, chlorination can occur at various positions, but due to the symmetry of the cyclohexane ring, there are only two distinct positions for substitution that lead to unique isomers.

**Hint:** Identify the positions on the cyclohexane ring where chlorine can be substituted to form different isomers.

### Step 4: Identify the Monochloro Isomers
In cyclohexane, the two unique monochloro isomers can be formed by substituting chlorine at:
1. One of the carbons in the ring (e.g., C1).
2. Another carbon in the ring that is not adjacent to the first substitution (e.g., C3).

These substitutions yield two distinct isomers due to the different spatial arrangements of the chlorine atom.

**Hint:** Visualize the cyclohexane structure to see how substituents can lead to different isomers.

### Conclusion
Based on the analysis:
- Compound A is cyclohexane (C₆H₁₂).
- It does not absorb H₂ in the presence of nickel.
- It forms two distinct monochloro isomers upon photochemical chlorination.

Thus, the structure of compound A can be concluded to be cyclohexane.

### Final Answer
The structure of compound A is cyclohexane (C₆H₁₂).