Note: This video is designed to help the teacher better understand the lesson and is NOT intended to be shown to students. It includes observations and conclusions that students are meant to make on ...

Evaporation is an endothermic process undertaken by all liquids. This physical state change occurs when surface molecules gain sufficient kinetic energy to overcome the enthalpy of vaporization. Such ...

Heating the water on the paper towel increases the motion of the water molecules. When the molecules have enough energy, they can move fast enough to break away from the attractions holding them to ...