Final answer:
According to Boyle's law, the pressure of a gas decreases if the volume of its container increases.
Step-by-step explanation:
According to Boyle's law, the pressure of a gas decreases if the volume of its container increases. Boyle's law states that the pressure and volume of a gas are inversely proportional to each other, meaning that as one variable increases, the other decreases. This relationship holds true as long as the temperature and amount of gas remain constant.