On the basis fo data given below predict which of the following gases shows least adsorption on a definite amount of charcoal?
`{:("Gas" ,,CO_(2),,SO_(2),,CH_(4),,H_(2)),("Critical temp./K",,304,,630,,190,,33):}`

Options

A. `CO_(2)`
B. `SO_(2)`
C. `CH_(4)`
D. `H_(2)`

Explanation

To determine which gas shows the least adsorption on a definite amount of charcoal, we need to analyze the given critical temperatures of the gases. The critical temperature indicates the temperature above which a gas cannot be liquefied, regardless of the pressure applied. Gases with higher critical temperatures can exist in a liquid state at higher temperatures and are generally more likely to be adsorbed on a solid surface like charcoal.

### Step-by-Step Solution:

1. **Identify the Critical Temperatures:**
- CO₂: 304 K
- SO₂: 630 K
- CH₄: 190 K
- H₂: 33 K

2. **Understand the Concept of Adsorption:**
- Gases with higher critical temperatures can be liquefied more easily and thus have a greater tendency to be adsorbed on surfaces like charcoal. This is because liquid molecules can interact more effectively with the surface than gas molecules due to their lower kinetic energy.

3. **Compare the Critical Temperatures:**
- Among the gases listed, H₂ has the lowest critical temperature (33 K). This means that at room temperature, H₂ will exist as a gas and will have a higher kinetic energy, leading to less adsorption on charcoal.
- In contrast, CO₂, SO₂, and CH₄ have higher critical temperatures, indicating that they can exist in a liquid state at higher temperatures and will therefore have a greater tendency to adsorb onto charcoal.

4. **Conclusion:**
- Since H₂ has the lowest critical temperature, it will show the least adsorption on a definite amount of charcoal compared to the other gases.

### Final Answer:
**H₂ shows the least adsorption on a definite amount of charcoal.**