======Liquid Nitrogen in Hot Water======


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**Alternative titles:** Liquid Nitrogen Dense Fog
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====Summary====                   
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====Procedure====  
  - Heat water in a beaker until it is nearly boiling.  
  - Place the beaker on a heat-safe surface in a well-ventilated area.  
  - Using insulated gloves, carefully pour liquid nitrogen into the hot water.  
  - Observe as the nitrogen boils violently and a thick, white fog rapidly forms above the beaker.  
  - Point out that the fog is not actually nitrogen, but condensed water droplets created by cooling the escaping water vapor.  




====Links==== 
Liquid Nitrogen and boiling water = FOG! - MrGrodskiChemistry: 
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====Variations====
  * Try using different temperatures of water (warm, hot, boiling) to compare the amount of fog produced.  
  * Use a strong flashlight or laser pointer to highlight the fog and make the droplets more visible.  
  * Place the beaker inside a large glass tank to contain the fog and create a dramatic rolling-cloud effect.  



====Safety Precautions====
  * Safety glasses required.  
  * Wear cryogenic gloves when handling liquid nitrogen.  
  * Use heat-resistant gloves if moving hot glassware.  
  * Perform in a well-ventilated area to prevent oxygen displacement.  
  * Use only borosilicate (Pyrex-type) glassware to reduce the risk of shattering.  
  * Stand back after pouring to avoid splashes of hot water or liquid nitrogen.  





====Questions to Consider====
  * Why does hot water produce more fog than warm water when liquid nitrogen is added?  
  * What exactly is the white cloud we see, and why isn’t it nitrogen gas?  
  * Why does cooling water vapor make it visible when it is normally invisible?  
  * How is this similar to the way clouds form in the atmosphere?  
  * Could this principle explain why you can sometimes “see your breath” on a cold day?