What happens to gas pressure when temperature decreases in a closed container?

When the temperature decreases in a closed container filled with gas, the kinetic energy of the gas molecules decreases. This reduced energy leads to slower-moving molecules, which results in fewer collisions with the walls of the container. Since gas pressure is defined as the force exerted by gas molecules colliding with the walls per unit area, a decrease in the frequency and intensity of these collisions leads to a corresponding decrease in pressure.

In this scenario, the gas pressure decreases as the temperature drops. The relationship between temperature and pressure in a closed system is described by Gay-Lussac's Law, which states that the pressure of a gas is directly proportional to its absolute temperature when the volume is held constant. Therefore, with a decrease in temperature, the pressure must also decrease.

The other choices reflect misunderstandings of gas behavior under changing temperature conditions. For instance, gas pressure can't remain constant if temperature decreases and volume is unchanged, as the kinetic energy directly impacts pressure. Similarly, while cooling gas can lead to condensation under certain conditions, this scenario typically involves a change in state rather than a straightforward decrease in pressure due to reduced temperature alone.