Materials Required:
l 5 tablespoons pure laundry soap or detergent
l 2 cups warm tap water
l 4 tablespoons salt
l Large glass
Procedure:
- Place the laundry soap into 1 cup of water. Stir until the soap is dissolved.
- Next, place the salt into another cup of water and stir until the salt is dissolved as much as possible.
- Pour the soap solution into a large glass, then pour the salt solution on top of it. Mix well. You will see the soap harden immediately and form a solid. If you let the mixture stand still for a few minutes, the soap will climb to the top of the solution and the bottom will remain clear.
This Is What Happens:
You have just demonstrated how a bar of soap is made. The process is called salting out the soap because the salt contains chemicals that react with the soap molecules, causing them to harden and settle out on top of the mass. Of course, soap manufacturers use large kettles. Usually the soap is removed before it hardens, and perfumes and colours are added to it. The soap can be placed in moulds, or allowed to harden and cut into bars.
