======How Salt Affects Freezing of Water======


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**Alternative titles:** Lowering the Freezing Point of Water
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====Summary====                   
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====Procedure====  
  -Label two bowls “Bowl 1” and “Bowl 2.”  
  -Pour water into each bowl.  
  -Add salt to Bowl 2, stirring until the salt is mostly dissolved.  
  -Place both bowls in the freezer at the same time.  
  -After one hour, check both bowls to observe any differences in freezing.  
  -Optional: use a thermometer to measure and record the temperature of each bowl.  
  -Leave the bowls for 24 hours and observe again to see which one froze completely.  
  -Discuss how the presence of salt affected the freezing rate and amount of ice formed.



====Links==== 
Saltwater Experiment - Susan Evans: 
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Freezing Point of Water Experiment | Chemistry - The Good and the Beautiful Homeschool Science: 
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📄 Freezing Water Experiment - Jane Bahrehbar: [[https://littlebinsforlittlehands.com/freezing-water/]]\\


====Variations====
  *Try adding different amounts of salt to see how concentration affects freezing rate.  
  *Test other substances such as sugar, baking soda, or vinegar to compare effects on freezing.
  *Measure and record temperature changes over time using a digital thermometer or data logger.



====Safety Precautions====
  *Handle glass or ceramic bowls carefully to prevent breakage when frozen.  
  *Do not taste or consume the saltwater samples.  
  *Wipe up any spilled water promptly to avoid slipping.  
  *Ensure bowls are placed securely in the freezer to prevent tipping or leaking.




====Questions to Consider====
  *Which bowl froze faster - plain water or saltwater? (Plain water.)  
  *Why did the saltwater take longer to freeze? (Salt lowers the freezing point of water.)  
  *What does this tell us about how salt affects molecular bonding during freezing? (Salt interferes with the ability of water molecules to form ice crystals.)  
  *How is this concept used in real life, such as when salt is spread on icy roads? (Salt lowers the freezing point of water, helping melt ice and prevent refreezing.)  
  *Is this a physical or chemical change? (Physical change, because no new substances are formed.)