Chemistry - Real Gas Question with Solution | TestHub
van der Waal constants for three different gases are given
Gas X: a = 3.0 atm l2/mol2, b = 0.025 l/mol
Gas Y: a = 10.0 atm l2/mol2, b = 0.030 l/mol
Gas Z: a = 6.0 atm l2/mol2, b = 0.035 l/mol
Which of the following is correctly matched?
Column I | Column II |
|---|---|
A) X | P) Maximum critical temperature |
B) Y | Q) Maximum critical volume |
C) Z | R) Least deviation from ideal behaviour |
| S) Maximum critical pressure |
Options:
Answer:
Solution:
Tc = 8a/27Rb: X ∝ 8(3)/(27×0.025) = 35.6; Y ∝ 80/0.81 = 98.8; Z ∝ 48/0.945 = 50.8, so Tc is maximum for Y (B→P). Vc = 3b: X = 0.075, Y = 0.090, Z = 0.105 l/mol, maximum for Z (C→Q). Pc = a/27b2: X = 3/(27×0.000625) = 177.8; Y = 10/(27×0.0009) = 411.5; Z = 6/(27×0.001225) = 181.4 atm, maximum for Y (B→S). Least deviation from ideality goes with the smallest a and b, i.e. X (A→R). Hence A→R; B→P,S; C→Q.
