Question

Dominance of strong repulsive force among the molecules of the gas where Z is the compressibility factor
A. Depends on Z and indicated by Z=1
B. Depends on Z and indicated by Z > 1
C. Depends on Z and indicated Z <1
D. Its independent of Z

Answer 1

Hint:
We should firstly discuss the deviation of a real gas from the ideal gas behaviour , the factor which shows this is called compressibility factor. Further we should look how active the repulsive forces are under such conditions.

Complete step by step answer:
Firstly discussing the compressibility factor which is the deviation of a real gas from the ideal gas behaviour , the factor which shows this is called compressibility factor.
We will find out that at high pressure the gas molecules are colliding very fast. This fast colliding makes the repulsive forces which exist between them more noticeable. Then we generally see that the molar volume of the real gas is higher than the molar volume of the ideal gas. As we know that a real gas is a gas, obey the gas laws under the specified conditions and further they show their existence as they are generally not negligible when the entire gas is concerned. Talking about the ideal gas it obeys gas laws under all condition of temperature and pressure and they do not mark a specific existence as their volume is considered negligible when the entire volume of gas is considered.as we have mentioned above that the molar volume of a real gas is more than that of an ideal gas which further causes Z to exceed one as the conditions are not purely ideal. When the strong repulsive forces among the gas molecules dominate then they make the compressibility factor to exceed from one . further there is one more fact and that is that more the gas is nearer to its critical point or its boiling the more is the deviation in the compressibility factor.
Hence, option B is correct which states that the dominance of strong repulsive force among the gas molecules depends on compressibility factor and further indicates that it is greater than one.

Note: In thermodynamics, a critical point is the end point of a phase equilibrium curve. The most prominent example is the liquid–vapor critical point, the end point of the pressure–temperature curve that designates conditions under which a liquid and its vapor can coexist.