Seeing two lines on a pregnancy test doesn’t necessarily mean you’re pregnant. The second line may be an evaporation line. This line can appear in the results window of a pregnancy test as the urine ...

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 ...

You know water evaporates - that's when it turns from a liquid to a gas. You probably also know that a hot pot of water will cool off in part because of evaporation. However, did you know that a cup ...