Here's why:
* Gas Laws: The behavior of gases is governed by laws like Boyle's Law and Avogadro's Law.
* Boyle's Law: This law states that at constant temperature, the volume of a gas is inversely proportional to its pressure. So, if you decrease the pressure, the volume will increase.
* Avogadro's Law: This law states that at constant temperature and pressure, the volume of a gas is directly proportional to the number of moles (and therefore, the number of molecules) of gas. Therefore, decreasing the number of molecules will decrease the volume.
Imagine a balloon: If you let some of the air out of a balloon, the balloon shrinks. This is because you've decreased the number of air molecules inside, causing the volume to decrease.
