At a constant volume, how does the pressure of a gas change with temperature?

The correct choice highlights a fundamental principle of gas behavior in physics known as Gay-Lussac's Law, which states that, at constant volume, the pressure of a gas is directly proportional to its absolute temperature. This means that as the temperature of the gas increases, its molecules gain kinetic energy, causing them to collide more frequently and forcefully with the walls of their container. This increased frequency and intensity of collisions result in higher pressure.

Conversely, if the temperature decreases, the kinetic energy of the gas molecules decreases, leading to less frequent and energetic collisions with the container walls, and therefore the pressure drops. This relationship presumes that the volume remains unchanged.

Understanding this principle is crucial in refrigeration systems, where gas pressure and temperature must be carefully managed to ensure efficient operation. When a refrigerant gas is compressed or expanded, its pressure and temperature will be manipulated to absorb or release heat effectively.

In this context, other options do not align with the established gas laws. For instance, if pressure were to remain constant regardless of temperature, it would not reflect the observations seen in practical applications or scientific experiments involving gases. Similarly, a notion that pressure is independent of volume changes isn't applicable under constant volume scenarios, as volume changes would directly influence pressure according