Question

Out of the gases $He, Ne, Kr$, and $Xe$, which one is least likely to obey the ideal gas laws at very high pressures and very low temperatures and why?

Answer 1

An ideal gas is a theoretical gas made up of a large number of randomly moving point particles with no interparticle interactions. Because it obeys the ideal gas law, a simplified equation of state, and is susceptible to statistical mechanics analysis, the ideal gas notion is helpful. If the interaction is fully elastic or viewed as point-like collisions, the criterion of zero interaction can frequently be waived.

Complete answer:
• The noble gases are a group of chemical elements with comparable characteristics; they are all odorless, colorless, monatomic gases with very little chemical reactivity under normal conditions.

• The noble gases are members of group 18 for the first six periods of the periodic table. Except under the most severe circumstances, noble gases are generally very inert.

• Noble gases' inertness makes them ideal for situations where no reactions are desired.
• Many actual gases behave qualitatively like an ideal gas under varied temperature and pressure circumstances, with gas molecules acting as ideal particles.

• Many gases, including noble gases and certain heavier gases like carbon dioxide, can be handled as ideal gases within tolerable tolerances throughout a wide temperature and pressure range.

• At higher temperatures and lower pressures, a gas behaves more like an ideal gas, as the potential energy due to intermolecular forces becomes less significant compared to the kinetic energy of the particles, and the size of the molecules becomes less significant compared to the empty space between them.
• The kinetic molecular theory of gases' postulates disregard both the volume filled by a gas's molecules and any interactions between molecules, whether attracted or repulsive.

• However, all gases have nonzero molecular volumes in actuality. Furthermore, the interactions between molecules in actual gases are dependent on the structure of the molecules and hence varies for each gaseous substance.
• Real gases vary substantially from ideal gas behavior at low temperatures or high pressures. It's also worth noting that the ideal gas law implies that gas molecules are small or non-existent.
• Keeping this in mind, because $Xe$ has the biggest mass and so occupies the most volume, it is predicted to deviate the most from the ideal gas when subjected to high pressure or low temperature.

Note:
• In both Newtonian dynamics (as in "kinetic theory") and quantum mechanics, the ideal gas model has been investigated (as a "gas in a box").

• The ideal gas model has also been used to represent the behavior of electrons in a metal (in the Drude and free electron models), and it is one of statistical mechanics' most important models.