In the eclipsed conformation of ethane, the dihedral ungle between the hydrogen atoms of adjacent methyl groups is

Options

A. `60^(@)`
B. `120^(@)`
C. `0^(@)`
D. `180^(@)`

Explanation

To determine the dihedral angle between the hydrogen atoms of adjacent methyl groups in the eclipsed conformation of ethane, we can follow these steps:

### Step 1: Understand the Structure of Ethane
Ethane (C2H6) consists of two carbon atoms bonded to each other, with three hydrogen atoms attached to each carbon. The molecular structure can be represented as:

```
H H
\ /
C - C
/ \
H H
```

### Step 2: Identify the Eclipsed Conformation
In the eclipsed conformation, the hydrogen atoms on one carbon atom are directly aligned with the hydrogen atoms on the adjacent carbon atom. This means that the hydrogen atoms from one carbon are positioned directly behind the hydrogen atoms from the other carbon.

### Step 3: Determine the Dihedral Angle
The dihedral angle is defined as the angle between two planes formed by four atoms. In the case of the eclipsed conformation of ethane, the angle between the hydrogen atoms on adjacent carbons is 0 degrees because they are directly overlapping each other.

### Conclusion
Thus, in the eclipsed conformation of ethane, the dihedral angle between the hydrogen atoms of adjacent methyl groups is **0 degrees**.

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