What does Charles' Law state regarding the volume of a gas at constant pressure?

Charles' Law describes how the volume of a gas is directly proportional to its temperature when the pressure is held constant. This relationship means that as the temperature of a gas increases, the volume also increases, provided that the pressure remains unchanged. The mathematical expression supporting Charles' Law can be written as V/T = k, where V is the volume, T is the temperature in Kelvin, and k is a constant for a particular gas at a given pressure. Thus, the correct understanding of this law clearly identifies that the volume of a gas will expand with an increase in temperature and contract with a decrease. This fundamental behavior of gases is critical in various applications and helps explain phenomena in thermodynamics.