PSC Do Science

Making of Soap Purpose

To create your own soap using a chemical process known as saponification. This is a reaction where an ester is heated with an alkali ( such as sodium hydroxide) to produce a free alcohol and an acid salt ( alkaline hydrolysis of a fat or oil ) to make soap.

You will use the highly alkaline chemical called lye and convert it into fats and fatty acids. Which will then yield soap.

Important notice: parental or teacher guidance required at all times. Due to the dangerous Lye.

Hypothesis:

Soap can be created from lye, lard, and olive oil.

Variables:

Amount of time it takes for soap to form.

Materials Needed:

1. Medium size pot
2. Large size pot
3. Baking pan
4. Large casserole dish that is made of glass
5. Glass jar
6. Thermometer
7. Electric blender
8. Measuring cup
9. Tablespoon
10. Wooden spoon
11. Cellophane wrap
12. Rubber Gloves
13. Goggles
14. 1.5 cups of lard
15. 0.5 cup of olive oil
16. Bottled distilled water
17. Lye grains or lye flakes

Procedures :

1. Fill the large pot halfway with tap water. Heat the water until it reaches a temperature of 95 degrees Fahrenheit. Remove the large pot from the flame.
2. Place the 1.5 cups of lard in the medium size pot. Use a low heat to melt the lard into a liquid. Add 0.5 cup of olive oil into the potand stir with the wooden spoon.
3. Pour the lard and olive oil mixture into the casserole dish, then lower the casserole dish into the large pot of water. Leave until the lard and olive oil mixture cool.
4. Pour 0.75 cup of bottle water into the glass jar.
5. It is time to add the Lye. Be very careful! Wear the face mask, covering nose and mouth. Do not breath in the dangerous fumes of gas. Find a well ventilated area. Add 2 teaspoons of lye into the glass jar filled already with water. Stir the mixture with a wooden spoon.
6. With great care, place the large casserole dish on a table. Pour the lye water into the casserole dish. Gently stir the mixture of lard, olive oil and lye with the wooden spoon. The saponification process will begin as the fat molecules react with the lye. Record your observations.
7. Use an electric blender to stir the mixture for about 15 minutes until its consistency is that of a loose custard and opaque colour.
8. Line the baking tray with cellophane , and gently pour the soap mixture into the tray. Cover the baking tray with more cellophane and leave for 24 hours.
9. By the next day your soap will be ready. But before you can use it, you will need to cut the soap into bars, then place them on wax paper. Allow to dry for at least 2 weeks. It will take more than 2 weeks for the alkaline in the soap to go away. Alkaline can cause skin irritation.

Summary of Results:

Lye ( sodium hydroxide ) is a chemical which is capable of breaking down fatty acids to create soap.

See also:

Biochemistry Science Fair Projects, Ideas, and Experiments

Flame reaction, Chemistry Experiment

Chemistry Experiment: Production of Carbon Dioxide