What is not applicable to ozone ?

Options

A. It is a bent molecule with bond angle approximately `117^@`
B. It has four lone pairs of electrons in one of its Lewis formula
C. The two O-O bond lengths are equal
D. It is an allotrope of oxygen.

Answer

To solve the question "What is not applicable to ozone?", we need to analyze each of the given options regarding the properties and structure of ozone (O3).

### Step-by-Step Solution:

1. **Understanding Ozone Structure**:
- Ozone is a molecule composed of three oxygen atoms (O3).
- The structure of ozone can be represented using Lewis structures, which show the arrangement of electrons.

2. **Analyzing Each Option**:
- **Option 1**: "It is a bent molecule with bond angle approximately 117 degrees."
- Ozone has a bent molecular geometry due to the presence of lone pairs on the central oxygen atom. The bond angle is approximately 116-117 degrees. This statement is **true**.

- **Option 2**: "It has 4 lone pairs of electrons in its Lewis formula."
- In the Lewis structure of ozone, we find that the central oxygen atom has one lone pair, while the other two oxygen atoms have two and three lone pairs, respectively. This totals to **6 lone pairs** (1 + 2 + 3 = 6), not 4. Therefore, this statement is **false** and not applicable to ozone.

- **Option 3**: "The 2 O-O bond lengths are equal."
- Ozone has resonance structures, which means that the two O-O bonds are not identical but have characteristics of both single and double bonds. However, due to resonance, the bond lengths are effectively equal. This statement is **true**.

- **Option 4**: "It is an allotrope of oxygen."
- Ozone (O3) is indeed an allotrope of oxygen, as it is a different form of the same element (oxygen). This statement is **true**.

3. **Conclusion**:
- The only statement that is not applicable to ozone is **Option 2**, which incorrectly states that ozone has 4 lone pairs of electrons.

### Final Answer:
The correct answer is **Option 2**: "It has 4 lone pairs of electrons in its Lewis formula."

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