Under which of the following conditions would the gases in the container most deviate from ideal conditions and why? (A) Low pressures, because the gas molecules would be spread far apart (B) High pressures, because the gas molecules will be colliding (C) Low temperatures, because the intermolecular forces between the gas molecules would increase (D) High temperatures, because the gas molecules are moving too fast to interact with each other

The Ideal Gas Law assumes that gases are composed of very small particles that are far apart relative to their size, there are no intermolecular forces between the particles, and that collisions between molecules are perfect, meaning no energy is lost. We need to find out under which conditions these assumptions are most likely to be violated.

(A) At low pressures, gas molecules are indeed spread far apart, which is actually in line with the assumptions of the Ideal Gas Law. Therefore, this does not represent a deviation from ideal conditions. (B) At high pressures, gas molecules will collide more frequently. However, the Ideal Gas Law assumes that these collisions are perfect, meaning no energy is lost. Real gases can deviate from this due to intermolecular forces and the physical volume of the molecules. Therefore, at high pressure, the behavior of real gases can deviate significantly from the assumptions of the Ideal Gas Law. (C) As temperatures decrease, the speed of the molecules decreases and the intermolecular forces can become more significant compared to the kinetic energy of the molecules. This can make the gas behave less ideally. (D) At high temperatures, gas molecules are moving fast, but this should not prevent them from interaction. The Ideal Gas Law does not contemplate a speed too high for interaction.

Given the analysis carried out in the previous step, it can be concluded that high pressures (option B) because the gas molecules will be colliding and low temperatures (option C) because the intermolecular forces between the gas molecules would increase, are the conditions where the gases would most deviate from ideal conditions. However, if we pick the single most deviating condition, it is usually the high pressure which represents a greater deviation from ideal conditions.