A gas at 350 K and 15 bar has molar volume 20 percent smaller than that for an ideal gas under the same conditions. The correct option about the gas and its compressibility factor (Z) is -
- Z < 1 and attractive forces are dominant
- Z < 1 and repulsive forces are dominant
- Z > 1 and attractive forces are dominant
- Z > 1 and repulsive forces are dominant
Answer
(1) Z < 1 and attractive forces are dominant
Solution
Compressibility factor:
Z = VrealVideal
Vreal = 0.8 Videal
Z = 0.8 < 1
As per NCERT, when Z < 1 the gas is more compressible than an ideal gas (negative deviation), because attractive forces between the molecules are dominant.
Answer: (1)