When a covalent bond is formed between two similar atoms, the shared pair of electrons is equally attracted by the two atoms. As a result of this, the electron pair is situated exactly in between two identical nuclei. The bond is known as non-polar covalent bond. On the other hand, if the atoms forming bonds are different, the electron attracting powers of the two atoms in a bond may differ. Consequently, the shared pair will be displaced towards the atom having more electronegativity.
Which one of the following is a non-polar covalent compound?

Options

A. `H_2O`
B. HF
C. `N_2`
D. `HI`

Explanation

To determine which of the following compounds is a non-polar covalent compound, we need to analyze the nature of the bonds formed in each compound. A non-polar covalent bond occurs when two identical atoms share electrons equally, resulting in no charge separation. Here’s a step-by-step approach to identify a non-polar covalent compound:

### Step 1: Understand the Definition of Non-Polar Covalent Bond
A non-polar covalent bond is formed when two identical atoms share a pair of electrons equally. This occurs because the electronegativity difference between the atoms is zero.

### Step 2: Identify the Compounds
List the compounds you are considering. For example, let's assume the options are:
- H2 (Hydrogen)
- H2O (Water)
- HF (Hydrogen Fluoride)
- N2 (Nitrogen)

### Step 3: Analyze Each Compound
1. **H2 (Hydrogen)**:
- Both atoms are hydrogen, which are identical.
- The electronegativity difference is 0.
- Therefore, H2 is a non-polar covalent compound.

2. **H2O (Water)**:
- Contains oxygen and hydrogen.
- Oxygen is more electronegative than hydrogen, leading to a polar bond.
- Thus, H2O is a polar covalent compound.

3. **HF (Hydrogen Fluoride)**:
- Contains hydrogen and fluorine.
- Fluorine is much more electronegative than hydrogen, resulting in a polar bond.
- Therefore, HF is a polar covalent compound.

4. **N2 (Nitrogen)**:
- Both atoms are nitrogen, which are identical.
- The electronegativity difference is 0.
- Therefore, N2 is also a non-polar covalent compound.

### Step 4: Conclusion
From the analysis, both H2 and N2 are non-polar covalent compounds. However, if we are to choose one, H2 is the most commonly recognized example of a non-polar covalent compound.

### Final Answer
**H2 (Hydrogen)** is a non-polar covalent compound.

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