The dihedral angle in gaseous `H_(2)O_(2)` is

Options

A. `111.5^(@)`
B. `90.2^(@)`
C. `94.8^(@)`
D. `101.9^(@)`

Answer

To determine the dihedral angle in gaseous H₂O₂ (hydrogen peroxide), we can follow these steps:

### Step 1: Understand the Structure of H₂O₂
Hydrogen peroxide has the molecular formula H₂O₂. Its structure consists of two oxygen atoms connected by a single bond, with each oxygen atom also bonded to a hydrogen atom. This creates a non-linear arrangement.

### Step 2: Draw the Lewis Structure
To visualize the dihedral angle, we can draw the Lewis structure of H₂O₂. The structure can be represented as:
```
H
|
O - O
|
H
```
Here, the two oxygen atoms are connected by a single bond, and each oxygen is bonded to a hydrogen atom.

### Step 3: Identify the Dihedral Angle
The dihedral angle is the angle between two planes formed by four atoms. In the case of H₂O₂, we can consider the two planes formed by the atoms:
1. Plane 1: H-O-O
2. Plane 2: O-H

The dihedral angle is the angle between these two planes.

### Step 4: Determine the Dihedral Angle Value
From experimental data and molecular geometry studies, it is known that the dihedral angle in gaseous H₂O₂ is approximately 111.5 degrees.

### Conclusion
Thus, the dihedral angle in gaseous H₂O₂ is **111.5 degrees**.

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