The Water Cycle
When the sun shines on the Earth it causes the water to evaporate (note the word "vapor") and go into the air. If the vapor rises high into the atmosphere, gets cold and then the molecules begin to stick together, condensation occurs and clouds form. If the clouds become saturated and can no longer hold the moisture, precipitation occurs in the form of rain, snow, sleet, freezing rain, or hail. Condensation and precipitation occur on a glass with a cold drink on a humid day, resulting in a water ring on the table. There is a common misconception that the water gets on the side of the glass when the glass "sweats". I explain to my students that in order to sweat, water has to come out of something, (like their armpits!) water doesn't come out of the glass.