The number of unpaired electrons in a parmamagnetic diatomic molecule of an element with atomic number ` 16` is :

Options

A. 2
B. 3
C. 4
D. 1

Explanation

To determine the number of unpaired electrons in a paramagnetic diatomic molecule of an element with atomic number 16, we will follow these steps:

### Step 1: Identify the Element
The element with atomic number 16 is sulfur (S). In its diatomic form, it is represented as \( S_2 \).

**Hint:** Look up the periodic table to find the element corresponding to atomic number 16.

### Step 2: Understand the Molecular Form
The diatomic molecule of sulfur is \( S_2 \). To analyze its electronic configuration, we can draw parallels with the diatomic oxygen molecule \( O_2 \), as they belong to the same group in the periodic table.

**Hint:** Consider the similarities in electronic configuration between elements in the same group.

### Step 3: Write the Molecular Orbital Configuration
For \( O_2 \), the molecular orbital configuration is:
- \( \sigma 1s^2 \)
- \( \sigma^* 1s^2 \)
- \( \sigma 2s^2 \)
- \( \sigma^* 2s^2 \)
- \( \sigma 2p_z^2 \)
- \( \pi 2p_y^2 \)
- \( \pi 2p_x^2 \)
- \( \pi^* 2p_y^1 \)
- \( \pi^* 2p_x^1 \)

This configuration shows that \( O_2 \) has a total of 16 electrons.

**Hint:** Familiarize yourself with the molecular orbital theory to understand how electrons fill the orbitals.

### Step 4: Identify Unpaired Electrons
From the molecular orbital configuration of \( O_2 \), we see that there are two unpaired electrons in the \( \pi^* 2p_y \) and \( \pi^* 2p_x \) orbitals. Since sulfur is in the same group as oxygen, we can infer that \( S_2 \) will have a similar configuration and also have two unpaired electrons.

**Hint:** Look for the orbitals that contain unpaired electrons in the configuration.

### Step 5: Conclusion
Thus, the number of unpaired electrons in the paramagnetic diatomic molecule \( S_2 \) is 2.

**Final Answer:** The number of unpaired electrons in \( S_2 \) is **2**.