The Vander Waal’s constant ‘a’ for the gases `O_(2), N_(2), NH_(3)` and `CH_(4)` are 1.3, 1.390, 4.170 and `2.253 l^(2)"atm" "mol"^(-2)` respectively. The gas which can be most easily liquefied is

Options

A. `O_(2)`
B. `N_(2)` and `O_(2)`
C. `NH_(3)`
D. `CH_(4)`

Answer

To determine which gas can be most easily liquefied among O₂, N₂, NH₃, and CH₄ based on the 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' represents the strength of intermolecular attractions in a gas. A higher value of 'a' indicates stronger attractive forces between gas molecules, which facilitates the liquefaction of the gas.

### Step 2: List the values of 'a' for the given gases
- O₂: a = 1.3 L² atm mol⁻²
- N₂: a = 1.390 L² atm mol⁻²
- NH₃: a = 4.170 L² atm mol⁻²
- CH₄: a = 2.253 L² atm mol⁻²

### Step 3: Compare the values of 'a'
From the values listed:
- O₂ has 'a' = 1.3
- N₂ has 'a' = 1.390
- NH₃ has 'a' = 4.170
- CH₄ has 'a' = 2.253

### Step 4: Identify the gas with the highest 'a' value
Among the gases listed, NH₃ has the highest Van der Waals constant 'a' value of 4.170 L² atm mol⁻².

### Step 5: Conclusion
Since NH₃ has the highest value of 'a', it indicates that it has the strongest intermolecular attractions among the gases considered. Therefore, NH₃ can be most easily liquefied.

### Final Answer
The gas which can be most easily liquefied is **NH₃**.

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