The values of van der Waals' constant 'a' for `O_2, N_2, NH_3 " and " CH_4 " are " 1.360, 1.390, 4.170 " and " 2.253 L^2 " atm " mol^(-2)` respectively. The most easily liquefiable gas among these is

Options

A. `N_2`
B. `NH_3`
C. `O_2`
D. `CH_4`.

Explanation

To determine the most easily liquefiable gas among O₂, N₂, NH₃, and CH₄ based on the given van der Waals constant 'a', we can follow these steps:

### Step 1: Understand the significance of the van der Waals constant 'a'
The van der Waals constant 'a' is a measure of the attractive forces between gas molecules. A higher value of 'a' indicates stronger intermolecular attractions, which typically leads to easier liquefaction of the gas.

### Step 2: List the values of 'a' for each gas
- For O₂: a = 1.360 L² atm mol⁻²
- For N₂: a = 1.390 L² atm mol⁻²
- For NH₃: a = 4.170 L² atm mol⁻²
- For CH₄: a = 2.253 L² atm mol⁻²

### Step 3: Compare the values of 'a'
Now, we will compare the values of 'a' for each gas to determine which one is the highest:
- O₂: 1.360
- N₂: 1.390
- NH₃: 4.170
- CH₄: 2.253

### Step 4: Identify the gas with the highest 'a' value
From the comparison, we see that NH₃ has the highest value of 'a' (4.170). This indicates that NH₃ has the strongest intermolecular attractions among the gases listed.

### Step 5: Conclusion
Since NH₃ has the highest van der Waals constant 'a', it is the most easily liquefiable gas among O₂, N₂, NH₃, and CH₄.

### Final Answer
The most easily liquefiable gas among O₂, N₂, NH₃, and CH₄ is **NH₃**.

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