Science at Home
Soap production
Science at Home


      Alcohol lamp.
      Tripod and metal net.
      Kitchen spoon.
      Latex gloves.

      Sodium hydroxide (caustic soda).
      Sodium chloride (salt).
      Distilled water.


     1. Attention! During the execution of this experiment you should protect your hands with gloves and eyes with glasses.

     2. Prepare a solution of sodium hydroxide. (be careful handling sodium hydroxide because it is very alkaline and dangerous. The hydroxide of sodium is usually supplied in solid pellets. Transfer some pellets to the beacker with water using a plastic spoon)

     3. Add fat to the sodium hydroxide solution. (you can use small piece of butter or some drops of oil)

     4. Heat the solution and let it boil during 20 minutes. (you should be careful because the solution is hot and very alkaline. If during the ebullition there are some drops outside the beacker, they should be immediately clean with a wet cloth)

     5. Pour the solution to another beacker, adding a spoon of sodium chloride (common salt) and some drops of perfume. Let the solution cool down. (you should be cautious handling the hot beacker, because as it is known, hot or cold glass seems the same)

     6. In the end, floating in the solution there is a solid that can be called as perfumed soap. (soap is good for cleaning because the chain of the soap molecules have an nonpolar that is given by the fat, and other polar part that is given by the salt and sodium hydroxide. Due to these characteristics, soap attracts polar or nonpolar molecules)

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