Evaporation and Condensation Directions: Read, Highlight, and Once You Are Finished Reading, Go to Schoology.Com to Answer Questions

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Name: ______________________________ Evaporation and Condensation Directions: Read, highlight, and once you are finished reading, go to schoology.com to answer questions. Evaporation Evaporation is the scientific name for liquid turning into a gas. The temperature where liquid turns into a gas is called the boiling point. Every substance on earth has a different boiling point. This should sound very similar to what you read for melting points. Water has a boiling point of 100oC (212oF), a temperature special to water only. As a liquid approaches its boiling point, the particles absorb more heat energy making them vibrate faster. When liquids reach their boiling point, the particles don’t continue to vibrate faster. You saw this when we boiled water (and when we melted ice). The heat goes into break the attraction the particles have to each other. When liquid particles gain enough energy to overcome the attraction holding them together, they become a gas. Once liquids become a gas, the molecules can move faster. Instead of sliding over each other like a liquid, they can fly around attracted to nothing. Molecules that are evaporating are absorbing heat. Because the molecules are absorbing heat, evaporation is called endothermic. Remember, endo means “to enter” while thermic means “heat.” Condensation The opposite of evaporation is condensation. Condensation happens when a gas changes back to a liquid. We see condensation happen every time clouds turn into rain. Clouds are a gas. Rain is a liquid. When the clouds turn into rain, condensation happens. Condensation happens because the gas loses heat energy. For water, condensation happens at 100oC (212oF). That same weird thing happens during condensation just like evaporation. The temperature stops until all of the gas has turned into a liquid. When, when the temperature stops, that is phase change. After all of the gas turns into a liquid, the temperature is free to drop more. Here is a fun science fact . Condensation and evaporation happen at the same temperature. So what is the difference? Evaporation is endothermic. For condensation the molecules are giving up their heat energy. When molecules give up heat energy, it is called exothermic. Condensation would be exothermic. Remember, exo means “to exit” while thermic means “heat.” Complete the following chart for Water Evaporation or Condensation Boiling Point Temperature where it occurs? Endothermic or Exothermic change? Temperature climbing or staying the same? Remember to go to schoology.com to complete your assignment. .

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