The value of van der Waals constant `a` is the maximum for

Options

A. chlorine
B. hydrogen
C. nitrogen
D. helium

Answer

To determine which gas has the maximum value of the van der Waals constant \( a \), we can follow these steps:

### Step-by-Step Solution:

1. **Understand the van der Waals Constant \( a \)**:
- The van der Waals constant \( a \) is a measure of the strength of intermolecular forces in a gas. A higher value of \( a \) indicates stronger attractive forces between gas molecules.

2. **Analyze the Given Gases**:
- The gases provided for comparison are:
- Chlorine (Cl₂)
- Hydrogen (H₂)
- Nitrogen (N₂)
- Helium (He)

3. **Consider the Nature of Each Gas**:
- **Chlorine (Cl₂)**: This is a diatomic molecule with strong covalent bonds. The molecules in Cl₂ have significant intermolecular attractions due to their size and polarity.
- **Hydrogen (H₂)**: This is a diatomic molecule with weak intermolecular forces. The attraction between H₂ molecules is relatively low.
- **Nitrogen (N₂)**: This is also a diatomic molecule, but it has moderate intermolecular forces compared to Cl₂.
- **Helium (He)**: This is a noble gas with very weak intermolecular forces due to its monoatomic nature and lack of polarity.

4. **Compare the Values of \( a \)**:
- Among the gases, Cl₂ has the strongest intermolecular forces due to its larger size and the presence of covalent bonds, leading to a higher value of \( a \).
- In contrast, He has the weakest intermolecular forces, resulting in the lowest value of \( a \).

5. **Conclusion**:
- Based on the analysis, chlorine (Cl₂) has the maximum value of the van der Waals constant \( a \) among the given gases.

### Final Answer:
The value of van der Waals constant \( a \) is the maximum for **Chlorine (Cl₂)**.

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