What law states that the pressure and volume of a gas are inversely proportional?

The law that states that the pressure and volume of a gas are inversely proportional is Boyle's Law. This relationship is described mathematically as P1V1 = P2V2, where P represents pressure and V represents volume. According to Boyle's Law, as the volume of a gas increases, its pressure decreases, provided the temperature and the number of moles of gas remain constant. This inverse relationship can be observed in practical situations; for example, when you compress a gas in a syringe, its volume decreases while its pressure increases, demonstrating the principles of Boyle's Law.

In contrast, Charles's Law deals with the relationship between volume and temperature, showing that volume expands with an increase in temperature. Gay-Lussac's Law describes the relationship between pressure and temperature at constant volume, where pressure increases with temperature. The Ideal Gas Law integrates these relationships along with the number of moles and the gas constant but does not specifically state the inverse relationship between pressure and volume. Therefore, Boyle's Law is the correct answer for this question.