Oxygen molecule is :

Options

A. Paramagnetic
B. Diamagnetic
C. Ferromagnetic
D. Ferrimagnetic

Answer

To determine the properties of an oxygen molecule (O₂), we can analyze its electronic configuration and molecular orbital (M-O) theory. Here’s a step-by-step solution:

### Step 1: Determine the number of electrons in an oxygen molecule
An oxygen molecule consists of two oxygen atoms. Each oxygen atom has 8 electrons, so:
\[ \text{Total electrons in O}_2 = 2 \times 8 = 16 \text{ electrons} \]

### Step 2: Write the molecular orbital configuration
According to molecular orbital theory, the electrons in an oxygen molecule fill the molecular orbitals in the following order:
1. \( \sigma_{1s} \) (2 electrons)
2. \( \sigma^*_{1s} \) (2 electrons)
3. \( \sigma_{2s} \) (2 electrons)
4. \( \sigma^*_{2s} \) (2 electrons)
5. \( \sigma_{2p_z} \) (2 electrons)
6. \( \pi_{2p_x} \) (2 electrons)
7. \( \pi_{2p_y} \) (2 electrons)
8. \( \pi^*_{2p_x} \) (1 electron)
9. \( \pi^*_{2p_y} \) (1 electron)

### Step 3: Count the electrons in the molecular orbitals
- The filling of the molecular orbitals for O₂ is:
- \( \sigma_{1s}^2 \)
- \( \sigma^*_{1s}^2 \)
- \( \sigma_{2s}^2 \)
- \( \sigma^*_{2s}^2 \)
- \( \sigma_{2p_z}^2 \)
- \( \pi_{2p_x}^2 \)
- \( \pi_{2p_y}^2 \)
- \( \pi^*_{2p_x}^1 \)
- \( \pi^*_{2p_y}^1 \)

### Step 4: Identify the presence of unpaired electrons
In the molecular orbital configuration for O₂, we see that there are two unpaired electrons in the \( \pi^*_{2p_x} \) and \( \pi^*_{2p_y} \) orbitals.

### Step 5: Determine the magnetic property
Since there are unpaired electrons in the oxygen molecule, it exhibits paramagnetism. This means that O₂ is attracted to a magnetic field.

### Conclusion
The oxygen molecule (O₂) is paramagnetic due to the presence of unpaired electrons in its molecular orbital configuration.

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