Which of the compounds shown below are isomers?

Options

A.
B.
C.
D.

Answer

To determine which of the compounds shown are isomers, we need to follow these steps:

### Step 1: Identify the Molecular Formula of Each Compound
First, we need to analyze the structures of the compounds provided and count the number of carbon (C) and hydrogen (H) atoms in each.

1. **First Compound**:
- Count the Carbons: 8 (C8)
- Count the Hydrogens: 12 (H12)
- Molecular Formula: C8H12

2. **Second Compound**:
- Count the Carbons: 8 (C8)
- Count the Hydrogens: 14 (H14)
- Molecular Formula: C8H14

3. **Third Compound**:
- Count the Carbons: 8 (C8)
- Count the Hydrogens: 14 (H14)
- Molecular Formula: C8H14

4. **Fourth Compound**:
- Count the Carbons: 8 (C8)
- Count the Hydrogens: 14 (H14)
- Molecular Formula: C8H14

### Step 2: Compare the Molecular Formulas
Next, we compare the molecular formulas of the compounds:

- The first compound has the formula C8H12.
- The second, third, and fourth compounds all have the formula C8H14.

### Step 3: Identify Isomers
Isomers are compounds that have the same molecular formula but differ in structure or arrangement.

- **C8H12** (First Compound) does not match with any of the others.
- **C8H14** (Second, Third, and Fourth Compounds) are isomers of each other since they all have the same molecular formula but different structural arrangements.

### Conclusion
The compounds that are isomers are the second, third, and fourth compounds (all C8H14). The first compound (C8H12) is not an isomer of the others.

### Final Answer
The compounds that are isomers are the second, third, and fourth compounds.

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