Which among the following is an example of polar molecule ?

Options

A. `O_(2)`
B. `H_(2)`
C. `N_(2)`
D. `HCl`

Explanation

To determine which among the given options is an example of a polar molecule, we can follow these steps:

### Step 1: Understand the Definition of a Polar Molecule
A polar molecule is characterized by the separation of positive and negative charges, resulting in a permanent dipole moment. This occurs when there is a significant difference in electronegativity between the atoms in the molecule.

### Step 2: Identify the Given Options
The options provided are:
1. O2 (Oxygen)
2. H2 (Hydrogen)
3. N2 (Nitrogen)
4. HCl (Hydrogen Chloride)

### Step 3: Analyze Each Option
- **O2 (Oxygen)**: This molecule consists of two oxygen atoms. Since both atoms are identical, they have the same electronegativity, making O2 a non-polar molecule.

- **H2 (Hydrogen)**: Similar to O2, H2 consists of two hydrogen atoms. They also have the same electronegativity, which classifies H2 as a non-polar molecule.

- **N2 (Nitrogen)**: N2 consists of two nitrogen atoms. Again, both atoms are the same, leading to the same electronegativity and classifying N2 as a non-polar molecule.

- **HCl (Hydrogen Chloride)**: This molecule consists of hydrogen and chlorine. These two atoms have different electronegativities (chlorine is more electronegative than hydrogen), which leads to a separation of charge and creates a dipole moment. Therefore, HCl is a polar molecule.

### Step 4: Conclusion
Based on the analysis, the example of a polar molecule among the options provided is **HCl (Hydrogen Chloride)**.