Explain why oxygen molecule exhibits paramagnetism?

Answer

To explain why the oxygen molecule exhibits paramagnetism, we can follow these steps:

### Step 1: Determine the number of electrons in an oxygen molecule
An oxygen atom has 8 electrons, so an oxygen molecule (O₂) will have a total of 16 electrons (8 from each oxygen atom).

### Step 2: Write the electronic configuration of the oxygen molecule
Using molecular orbital theory, we can determine the electronic configuration of the oxygen molecule. The configuration is as follows:
- σ1s²
- σ*1s²
- σ2s²
- σ*2s²
- σ2p_z²
- π2p_x²
- π2p_y²
- π*2p_x¹
- π*2p_y¹

### Step 3: Identify the number of unpaired electrons
From the molecular orbital configuration, we can see that the last two electrons are in the π*2p_x and π*2p_y orbitals. Both of these orbitals contain one electron each, which means there are 2 unpaired electrons in the oxygen molecule.

### Step 4: Explain the concept of paramagnetism
Paramagnetism is a property of substances that have unpaired electrons. These unpaired electrons create a magnetic moment, which causes the substance to be weakly attracted to a magnetic field.

### Step 5: Conclude why the oxygen molecule is paramagnetic
Since the oxygen molecule (O₂) has 2 unpaired electrons, it exhibits paramagnetism. This means that O₂ is weakly attracted to a magnetic field due to the presence of these unpaired electrons.

### Summary
The oxygen molecule exhibits paramagnetism because it has 2 unpaired electrons in its molecular orbital configuration, leading to a magnetic moment that allows it to be attracted to magnetic fields.

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