Pick out the alkane which differs from the other members of the group.

Options

A. 2,2-dimethylpropane
B. pentane
C. 3-methylbutane
D. 2,2-dimethylbutane

Explanation

To solve the question of identifying the alkane that differs from the other members of the group, we will follow these steps:

### Step 1: Understand the Types of Hydrocarbons
Hydrocarbons are organic compounds made up of hydrogen and carbon atoms. Alkanes are a specific type of hydrocarbon that contain only single carbon-carbon bonds.

### Step 2: Identify the Given Alkanes
We need to analyze the given alkanes. The question does not specify the exact alkanes, but we can assume they are similar to those mentioned in the transcript, which includes:
1. 2,2-Dimethylpropane
2. Pentane
3. 3-Methylbutane
4. 2,2-Dimethylbutane

### Step 3: Determine the Molecular Formula of Each Alkane
Next, we will write the molecular formula for each alkane:
1. **2,2-Dimethylpropane**:
- Structure: C5H12
- Molecular Formula: C5H12
2. **Pentane**:
- Structure: C5H12
- Molecular Formula: C5H12
3. **3-Methylbutane**:
- Structure: C5H12
- Molecular Formula: C5H12
4. **2,2-Dimethylbutane**:
- Structure: C6H14
- Molecular Formula: C6H14

### Step 4: Compare the Molecular Formulas
Now, we will compare the molecular formulas:
- 2,2-Dimethylpropane: C5H12
- Pentane: C5H12
- 3-Methylbutane: C5H12
- 2,2-Dimethylbutane: C6H14

### Step 5: Identify the Odd One Out
From the comparison, we can see that the first three alkanes (2,2-Dimethylpropane, Pentane, and 3-Methylbutane) all have the same molecular formula (C5H12), while 2,2-Dimethylbutane has a different molecular formula (C6H14).

### Conclusion
Therefore, the alkane that differs from the other members of the group is **2,2-Dimethylbutane**.

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