That the conventional representation of oxygen molecule
`:ddotO: " " :ddotO:` Is wrong is suggested by the fact that

Options

A. oxygen is a colourless gas
B. oxygen atoms join to form the triatomic ozone molecule
C. oxygen is paramagnetic
D. oxygen is highly reactive

Explanation

To solve the question regarding the conventional representation of the oxygen molecule (O₂) and why it is considered incorrect, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Conventional Representation**:
The conventional representation of the oxygen molecule is given as `:O: :O:` which indicates that all electrons are paired. This implies that each oxygen atom in the molecule has its valence electrons paired.

2. **Identifying the Nature of Oxygen (O₂)**:
Oxygen (O₂) is known to be a diatomic molecule. According to molecular orbital theory (MOT), the electronic configuration of O₂ shows that it has unpaired electrons.

3. **Paramagnetism of O₂**:
One of the key characteristics of O₂ is that it is paramagnetic. This means that it has unpaired electrons that can be attracted to a magnetic field. The presence of unpaired electrons is a definitive property of paramagnetic substances.

4. **Conclusion**:
Since the conventional representation suggests that all electrons are paired, it contradicts the fact that O₂ is paramagnetic due to the presence of unpaired electrons. Therefore, the conventional representation is incorrect.

### Final Answer:
The conventional representation of the oxygen molecule is wrong because oxygen (O₂) is paramagnetic, which indicates the presence of unpaired electrons.

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