All the isomers with molecular formula `C_6H_(12)` that contain a cyclobutane ring.

Options

A. 5
B. 6
C. 7
D. 8

Answer

To find all the isomers with the molecular formula C6H12 that contain a cyclobutane ring, we can follow these steps:

### Step 1: Identify the base structure
The base structure is cyclobutane, which has four carbon atoms in a ring. To achieve a molecular formula of C6H12, we need to add two more carbon atoms.

### Step 2: Determine possible substituents
We can add substituents (alkyl groups) to the cyclobutane ring. The possible substituents can be methyl (C1H3) groups since they are the simplest alkyl groups.

### Step 3: List the isomers
1. **Cyclohexane**: This is a cyclic structure with no substituents.

2. **1-Methylcyclopentane**: This structure has a cyclobutane ring with one methyl group attached to it.

3. **1,3-Dimethylcyclobutane**: This structure has two methyl groups attached to the cyclobutane ring at the 1 and 3 positions.

4. **1,2-Dimethylcyclobutane**: This structure has two methyl groups attached to the cyclobutane ring at the 1 and 2 positions.

5. **1,2,3-Trimethylcyclopropane**: This structure has three methyl groups attached to a cyclopropane ring, which is a derivative of cyclobutane.

### Step 4: Count the isomers
After listing the structures, we find that there are a total of **five distinct isomers** of C6H12 that contain a cyclobutane ring.

### Conclusion
The total number of isomers with the molecular formula C6H12 that contain a cyclobutane ring is **five**.

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