What effect does the addition of gas molecules to a closed container have on pressure, assuming temperature remains constant?

When gas molecules are added to a closed container while maintaining a constant temperature, the pressure within the container increases. This effect can be attributed to the behavior of gas molecules in a confined space as described by the ideal gas law, which states that pressure is directly proportional to the number of gas molecules (or moles) present, provided that the volume and temperature remain constant.

As additional gas molecules are introduced, they occupy space within the container and collide more frequently with the walls of the container. Each collision exerts a force on the walls, leading to an increase in pressure. This relationship indicates that an increase in the number of gas molecules results in a direct increase in pressure, as long as the system's temperature does not change.

In essence, because temperature is kept constant, the kinetic energy of the gas molecules remains stable, and the increased number of collisions from the added molecules translates directly into higher pressure, aligning with the principles of gas behavior outlined in the kinetic molecular theory.