======Comparing Evaporation Rates======


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**Alternative titles:** Evaporation and Intermolecular Forces
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====Summary====                   
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====Procedure====  
  -Set up a temperature sensor connected to a data collection device.  
  -Place a small amount of the first liquid (e.g., water) on the sensor and record the temperature change as it evaporates.  
  -Repeat the test with other liquids (e.g., ethanol, acetone, or isopropyl alcohol).  
  -Compare the rate and extent of cooling for each liquid.  
  -Use molecular model sets to build structures of the tested liquids.  
  -Discuss how hydrogen bonding and molecular size influence evaporation rates.



====Links==== 
VIDEO_TITLE - AUTHOR: 
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📄 Evaporative Cooling - PASCO: [[https://www.pasco.com/resources/lab-experiments/603?srsltid=AfmBOor3X1mRz5qCG4PEqijMf4lMTA8WfcJ94GkcIW6wjPfwAYfME3o5]]\\

====Variations====
  * Use regular thermometers rather than temperature probes.
  * Test additional compounds such as hexane or glycerol.  
  * Compare evaporation rates under different airflow conditions (fan vs. still air).




====Safety Precautions====
  * Wear safety glasses. 
  * Perform in a well ventilated area. 
  * Do not ingest or inhale vapors from volatile liquids.  
  * Keep all alcohols and acetone away from open flames or heat sources.  
  * Wash hands after handling chemicals.




====Questions to Consider====
  * Which liquid evaporated the fastest? (Likely acetone or alcohol, due to weaker intermolecular forces.)  
  * Why does water evaporate more slowly than alcohols? (Because water molecules form strong hydrogen bonds that require more energy to break.)  
  * How do molecular structures relate to evaporation rates? (More hydrogen bonding and stronger attractions slow evaporation.)  
  * How does this demonstration connect to sweating and cooling in living systems? (Evaporation removes heat, helping regulate temperature.)