Is there an experiment I could do to prove that soap is made up of fat and lye?

Thank you for using the Jiskha Homework Help Forum. Here is a recipe for making soap:

Recipes From Scratch
Basic Recipes

Soap Crafters Castile (Non-veggie)
26 ounces of Olive Oil
60 ounces of Lard
11 ounces of Lye
32 ounces of Water
1.6 ounces of Soap Crafters Cold Process Soap Fragrance
Tracing happens in about an hour or so. If you stir for an hour and a half and it still hasn't traced, just put it into your plastic lined box mold. It should be fine.
This would be in the hard category of soap. It is quite white and resembles the color of cream cheese. :) When I was making my first batches of soap I used this recipe. When ever company came over and saw my bars of soap drying in the living room, they asked if it was cheese and they kinda wanted to eat it. But I wouldn't let them. ;)

There are many dangers working with lye:

http://www.pioneerthinking.com/soaps.html

While conducting an experiment to prove that soap is made up of fat and lye can be challenging and potentially hazardous due to the use of lye, there is a safer alternative that can help you understand the basic process.

One way to demonstrate the relationship between fat and lye in soap making is through a simple demonstration called "Saponification." Here's how you can do it:

Materials needed:
- Vegetable oil or fatty substance (such as lard or butter)
- Sodium hydroxide (lye)
- Safety goggles
- Rubber gloves
- Protective clothing
- Heat-resistant container
- Stirring utensil
- pH paper or pH indicator strips
- Optional: Fragrance or essential oils for scent

Procedure:
1. Prepare a well-ventilated area and wear safety goggles, rubber gloves, and protective clothing to ensure your safety.
2. Place a heat-resistant container on a heat source (such as a stovetop burner) and turn on the heat to medium-low.
3. Add a measured amount of vegetable oil or fatty substance (e.g., lard or butter) to the container.
4. Gradually add a measured amount of sodium hydroxide (lye) to the container while stirring continuously. The ratio of fat to lye should be in accordance with a soap recipe.
Note: Be very cautious when handling lye, as it is a caustic substance. Follow safety precautions and read the instructions provided by the manufacturer.
5. Continue stirring until the mixture reaches a thick, pudding-like consistency. This process is called "tracing." You can also add fragrance or essential oils at this stage if desired.
6. Allow the mixture to cool and harden for several hours or overnight.
7. After solidification, carefully remove the soap from the container and cut it into smaller bars or shapes.
8. Test the pH of the soap using pH paper or pH indicator strips. The pH should be around 9-10, indicating that the soap has undergone saponification.
9. Use the soap for handwashing or other suitable purposes.

Remember to prioritize safety when performing this experiment and follow all precautions when working with lye. It is essential to understand the potential hazards associated with lye and take necessary precautions to protect yourself and others.

Additionally, it's worth noting that this experiment will not provide definitive scientific evidence of the chemical composition of soap. For a more accurate analysis, specialized laboratory methods, such as gas chromatography or elemental analysis, would be required.