which gas is adsorbed to maximum amount by activated carbon ?

Options

A. `H_(2) (g)`
B. `He(g)`
C. `CO(g)`
D. `CO_(2)(g)`

Answer

To determine which gas is adsorbed to the maximum amount by activated carbon, we can follow these steps:

### Step 1: Understand Adsorption
Adsorption is the process by which gas molecules adhere to the surface of a solid. The extent of adsorption depends on various factors, including the properties of the gas and the adsorbent material.

### Step 2: Consider Critical Temperature
The critical temperature of a gas is the temperature above which it cannot be liquefied, regardless of the pressure applied. Gases with higher critical temperatures tend to have stronger intermolecular forces, which can lead to higher adsorption on activated carbon.

### Step 3: Compare Critical Temperatures of Gases
- Hydrogen and Helium have very low Van der Waals forces and low critical temperatures.
- Carbon dioxide (CO2) has a critical temperature of approximately 304.3 K.
- Carbon monoxide (CO) has a critical temperature of around -224°F (approximately -143.3°C or 130.8 K).

### Step 4: Analyze Van der Waals Forces
Gases with stronger Van der Waals forces are more likely to be adsorbed. Since CO2 has a higher critical temperature than CO, it indicates that CO2 has stronger intermolecular forces.

### Step 5: Conclusion
Given that CO2 has a higher critical temperature and stronger Van der Waals forces compared to CO, it is concluded that carbon dioxide is adsorbed to the maximum amount by activated carbon.

### Final Answer
**Carbon Dioxide (CO2)** is the gas that is adsorbed to the maximum amount by activated carbon.

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