======Evaporative Cooling with Liquids======


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**Alternative titles:** Evaporation and Cooling
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====Summary====                   
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====Procedure====  
  -Prepare one cup with a tablespoon of water and another with a tablespoon of rubbing alcohol.  
  -Use a pipet to place a few drops of water on the back of your hand and spread it with your fingers.  
  -Blow gently over the damp skin and note any temperature changes or sensations.  
  -Rinse the pipet, then use it to place a few drops of rubbing alcohol on the back of your other hand.  
  -Spread the alcohol and blow gently over it. Compare the sensation to the water.  
  -Record which liquid produced a greater cooling effect.



====Links==== 
Cooling by Evaporation Activity - Homemade Science with Bruce Yeany:
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📄 Evaporative Cooling with Liquids - Science Buddies: [[https://www.sciencebuddies.org/stem-activities/evaporative-cooling-with-liquids]]\\

====Variations====
  * Compare evaporation rates of alcohol and water by placing equal amounts in cups in the sun and monitoring how long they take to evaporate.



====Safety Precautions====
  * Do not ingest rubbing alcohol.  
  * Avoid contact with eyes or open cuts.  
  * Wash hands thoroughly after the experiment.  
  * Dispose of unused rubbing alcohol by flushing it down the sink with plenty of water.  
  * Conduct the experiment in a ventilated area.




====Questions to Consider====
  * Why does alcohol feel colder than water when it evaporates? (Because alcohol evaporates faster due to its lower boiling point, it removes heat from the skin more quickly.)  
  * How does blowing on the liquid affect evaporation? (It increases airflow, which speeds up evaporation and enhances cooling.)  
  * Why does sweating help regulate body temperature? (Sweat absorbs body heat during evaporation, carrying it away and cooling the body.)  
  * Which environmental factors influence evaporation rates? (Temperature, airflow, surface area, and the type of liquid.)