In which of the following subtances, intermolecular force of attraction is the maximum?

Options

A. Iron bar
B. Water
C. Air
D. Nitrogen

Explanation

To determine which of the following substances has the maximum intermolecular force of attraction, we can follow these steps:

### Step 1: Understand Intermolecular Forces
Intermolecular forces are the forces of attraction that exist between molecules. They vary in strength depending on the state of matter: solids, liquids, and gases.

### Step 2: Compare States of Matter
- **Solids**: Molecules are closely packed together, resulting in strong intermolecular forces.
- **Liquids**: Molecules are less tightly packed than in solids, leading to moderate intermolecular forces.
- **Gases**: Molecules are far apart, resulting in weak intermolecular forces.

### Step 3: Analyze the Given Options
1. **Iron Bar**: This is a solid. Therefore, it has strong intermolecular forces.
2. **Water**: This is a liquid. It has moderate intermolecular forces.
3. **Air**: This is a gas. It has weak intermolecular forces.
4. **Nitrogen**: This is also a gas, with weak intermolecular forces.

### Step 4: Determine the Maximum Intermolecular Force
Since solids have the strongest intermolecular forces, the iron bar, being a solid, will have the maximum intermolecular force of attraction compared to the other options.

### Conclusion
The substance with the maximum intermolecular force of attraction is the **iron bar**.

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