The vander waal's constant "a" for gases P,Q,R and S are 4.17 , 3.59 , 6.71 & 3.8 atm `L^(2) " mol"^(-2)` . Therefore , the ascending order of their ease of liquefaction is :-

Options

A. `RltPltSltQ`
B. `QltSltRltP`
C. `QltSltPltR`
D. `RltPltQltS`

Answer

To determine the ascending order of the ease of liquefaction of gases P, Q, R, and S based on their 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 forces, which generally leads to a greater ease of liquefaction.

### Step 2: List the given values of the Van der Waals constant "a"
- For gas P: \( a = 4.17 \, \text{atm L}^2 \text{mol}^{-2} \)
- For gas Q: \( a = 3.59 \, \text{atm L}^2 \text{mol}^{-2} \)
- For gas R: \( a = 6.71 \, \text{atm L}^2 \text{mol}^{-2} \)
- For gas S: \( a = 3.8 \, \text{atm L}^2 \text{mol}^{-2} \)

### Step 3: Arrange the gases based on the values of "a"
To find the ascending order of ease of liquefaction, we need to arrange the gases from the lowest to the highest value of "a":
- Q: \( 3.59 \)
- S: \( 3.8 \)
- P: \( 4.17 \)
- R: \( 6.71 \)

### Step 4: Write the ascending order of ease of liquefaction
Based on the values arranged, the ascending order of ease of liquefaction is:
- Q < S < P < R

### Final Answer
The ascending order of the ease of liquefaction of gases P, Q, R, and S is:
**Q < S < P < R**

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