Which law states that the volume of a gas is inversely proportional to its pressure at constant temperature?

Boyle's Law articulates the relationship between the pressure and volume of a gas when the temperature is held constant. According to this law, as the pressure of a gas increases, its volume decreases, and conversely, as the pressure decreases, the volume increases. This relationship arises because gas molecules, when compressed, have less space to move, resulting in increased collisions against the walls of the container, thereby raising the pressure.

In formal terms, Boyle's Law can be expressed mathematically as ( P \propto \frac{1}{V} ) at a fixed temperature, illustrating the inverse nature of the relationship. Consequently, if you were to plot the pressure of a gas against its volume, you'd see a hyperbolic curve demonstrating this inverse proportionality.

By contrast, other laws address different aspects of gas behavior: Charles's Law focuses on how gas volume changes with temperature, Avogadro's Law relates volume to the amount of gas, and Dalton's Law discusses the pressure contributions of different gases in a mixture. Thus, the fundamental principle established by Boyle's Law regarding pressure and volume stands distinct, confirming the correctness of identifying it as the governing law for this question.