Here's why:
* Inverse Proportionality: This means that as the pressure increases, the volume decreases, and vice versa, while keeping the product of pressure and volume constant.
* Constant Temperature: If the temperature changes, the gas molecules will move faster or slower, affecting their collisions with the container walls and changing the pressure.
* Constant Amount of Gas: If the amount of gas changes, the number of molecules colliding with the container walls changes, affecting the pressure.
In summary, Boyle's Law only applies when the temperature and amount of gas are held constant.
