Which of the following bicyclic compounds are isomers?

Options

A.
B.
C.
D.

Answer

To determine which bicyclic compounds are isomers, we need to follow these steps:

### Step 1: Identify the Bicyclic Compounds
We are given four options of bicyclic compounds. A bicyclic compound is defined as a compound that contains two interconnected rings.

### Step 2: Count the Number of Carbon Atoms
For each compound, we need to count the number of carbon atoms (C) present in the structure.

- **Option 1:** Count the carbon atoms in the structure.
- **Option 2:** Count the carbon atoms in the structure.
- **Option 3:** Count the carbon atoms in the structure.
- **Option 4:** Count the carbon atoms in the structure.

### Step 3: Count the Number of Hydrogen Atoms
Next, we will count the number of hydrogen atoms (H) in each compound.

- **Option 1:** Count the hydrogen atoms.
- **Option 2:** Count the hydrogen atoms.
- **Option 3:** Count the hydrogen atoms.
- **Option 4:** Count the hydrogen atoms.

### Step 4: Determine the Molecular Formula
After counting the carbon and hydrogen atoms, we can write the molecular formula for each compound in the form CxHy.

### Step 5: Compare the Molecular Formulas
Now we will compare the molecular formulas of all the options. If two or more compounds have the same molecular formula but different structural arrangements, they are considered isomers.

### Step 6: Conclusion
Based on the comparison of molecular formulas:
- If all options have the same molecular formula (C10H18 in this case), then they are isomers.

### Final Answer
All four options (1, 2, 3, and 4) are bicyclic compounds and they are isomers because they share the same molecular formula (C10H18) but have different structural arrangements.

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