According to Charle's Law, what happens to gases when they are heated?

According to Charles's Law, gases will expand when they are heated. This principle states that when the temperature of a gas increases, the volume also increases, provided the pressure remains constant. This relationship between temperature and volume reflects the kinetic theory of gases, where an increase in temperature leads to an increase in the energy of the gas particles. As these particles move faster, they collide with each other and the walls of their container more forcefully and frequently, causing the gas to occupy a larger volume.

The other options do not accurately reflect the relationship illustrated by Charles's Law. For instance, gases do not contract when heated; instead, they occupy more space. Evaporation is a process related to liquids transitioning into gas and doesn't directly pertain to the heating of gases themselves. Lastly, condensation involves the transition from gas to liquid as temperature decreases, which is opposite to the expansion described by Charles's Law. Thus, the principle clearly highlights that heating a gas results in its expansion.