Science at Home
Soap tubes
Science at Home

Materials

      Big basin.
      Wire.
Compounds

      Water.
      Detergent.
      Glycerin.
 
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Procedure

     1. Make a circle with the metal wire. (the wire should have a thickness that allows you to mold it with your hands)

     2. Pour half glass of detergent in the basin. (the detergent is essential)

     3. Adds 1 liter of water to the detergent.

     4. Add 60 milliliters of glycerin to the detergent solution.

     5. Mix the solution and leave it to rest during one night.

     6. Dive the metal wire circle in the solution.

     7. Lift the circle out of the solution and observe the formed soap tube. Enjoy science at home! (I got tubes of 3 meters. If they don't last very much, add more detergent and glycerin to the solution)
 
Why?

In the surface of water it exist a very known phenomenon - superficial tension. Due to superficial tension of water we don't obtain tubes without adding detergent to it. When we add detergent to water, the superficial tension decreases, facilitating the formation of soap tubes. The resulting soap tubes don't last for long time, because the water film evaporates very fast. Using glycerin, the speed of water evaporation is slower and the tubes last much more time. When we have rainy days the soap tubes will last even more time. Try it!
 




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