Ben Glenn Making Soap With Chemistry

Introduction: Ben Glenn Making Soap With Chemistry

Without soap this world would literally be a mess! Going to the store to pick soap up is easy, but what if you want to personalize it, make it your own, create something, well that is what I am here to teach you.

Soap can come from many different types of oils and fats making the possibilities of combinations endless. WAIT one second, yes I did just say soap is made out of fats and oils, and I will be getting to that. But before any of that sciency mumbo jumbo you need the equipment.

These instructions will be taking you though the hot process of making soap. It does require some learning as well. Hopefully your soap turns out just the way you want it !

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Step 1: Collecting Your Materials

Before even staring the creation of your soap you will need a few things. These materials are all fairly easy to come by and can be substituted by something that can do that same job just as well.

  1. A hot plate that can keep your oils and fats while mixing at a steady 45-54 degrees centigrade.
  2. Thermometer to keep a constant check on the temperature of your oils and soap mixture.
  3. A stir rod or some way to keep your mixture mixing (if possible get a hot plate with a magnetic stirring option it helps).
  4. A scale to weigh your fats and oils along with your lye/sodium hydroxide.
  5. Of course something to hold your ingredients in being a 1 liter beaker for the best accuracy of measurement and safety.
  6. You may want some molds for your soap to go into after the mixing has been completed. (anything that can hold water can most likely hold soap).

Once you have collected all of these things then you can figure out your selection process for the fats, oils, and other additives you may want to include. That moves us on to the make step...

Step 2: Selection of Fats and Oils

This is the most important step for the creation of the soap you want. Depending on the oils and fats you pick will change how much it cleans, how many bubbles it produces, if it is soft or hard.

To make this step a lot easier people out there have created a website called Soap Calculator. That link will take you to a website that will have all the different oils and fats you can think of. You Pick out which ones you have or want and then add what percentage or how many grams of each you will add. Now this is where you have to do a little research. They're so many different combinations its good to explore and find what you like.

For my soap I used only Crisco shortening and 100% olive oil. Now I used 100 grams of crisco and 50 grams of olive oil. If you put this into the calculator you see it's not the best soap. This soap is definitely still fun to make though.

At the left hand side you can see at the bottom of the list INS. You want that to be around 160 for a good soap

Step 3: A Little Bit Fat of Science

Fats and Oils come in three different types or are described this way(Saturated fats, Monounsaturated, and Polyunsaturated). These different types of fats react differently when creating soap. The soap calculator makes it easy to see how they will react and what it will turn out like.

Each fat and oil has their fatty acid chains. There is an acid attached to the top and a chain of carbon and hydrogen at the end. The longer and straighter a fatty acid chain is the higher the melting point for the molecules to split apart.

A saturated fat has a long straight chain that bonds very well together. For example shortening. A monounsaturated fat is a fatty acid chain with one double carbon bond bending the chain. For example olive oil. A Polyunsaturated fat has more then just one double carbon bond bending your fatty acid chain a lot. For example coconut oil can be this.

Some of the best soap uses a mixture of monounsaturated fats and polyunsaturated fats. Some of the best soap comes from a combination of coconut oil, olive oil and tallow(beef fat). They react in a way that evenly disperses the job the soap has to do.

Step 4: Saponification Value (Sap) Calculations and Information

This is one of the most important steps in the soap making process. This can make or break your whole soap experience.

To elaborate on that, the Saponification Value or Sap value for short is the amount of lye you will need to react with the triglycerides you are using to create the soap. The four molecules that are included in this are the triglyceride and the lye on the reactants side and the glycerol and soap on the other.

On the molecular scale the fat (triglyceride) and the lye are reacting. The lye separates the glycerol from the fat and the lye attaches to the carbon hydrogen chain. This molecule that we call soap is now created. Before the oil/fat could not be cleaned off because water and fat are polar and non polar molecules. Now the soap has been created so when water reacts with the soap it will make any fat molecule find a few other to make a ball. Once with molecular ball is formed it will just wash right off of your hands.

Easy enough for you the Sap value can easily be given by imputing all of your fats and oils into the Soap Calculator . At the Bottom you will see NaOH SAP and that is the number of reactants you will need.

In my example my NaOH SAP value was just about .136. This means for every 1 gram of fat I used .136 grams of sodium hydroxide to react with it.

Now the soap calculator does change the number slightly so you add 5% less then a perfect reaction so you do not come out with a to basic of a soap. If you are not safe in the way you measure out your ingredients your soap can become weak and you will be rubbing fat all over yourself. On the other hand you could be burning your skin off if you add to much sodium hydroxide.

Step 5: Ingredients and Sodium Hydroxide

Once you have picked your ingredients and found the sap value for your soap then you should be here. You will want the percentage of each type of oil and fat that is calculated when you used the soap calculator .

You will want to weight out each of your fats and oils then put them into your beaker and heat them up until they are all melted and between the temperature 45-54 degrees centigrade. Make sure to keep the fat mixing.


Lye if it comes into contact with your skin or your eyes will burn you and can pertinently blind you!!!

Make sure to be wearing all necessary cloths (gloves, long sleeves, indirectly vented goggles). Now you are ready to weight out how much lye you need. Take that SAP value and however grams of total fat you are using just multiple to get how many grams you will need.


Once ALL of the fat is liquefied in your beaker then slowly pour in your lye being careful not to splash it.


Step 6: Mixing and Heating the Mixture

Once you have added all of your lye to the fats and you are at a constant temperature while mixing you just have to wait. It can take anywhere from 5 min to 1 hour+.

You will know when your soap is at the end of the heating and mixing process becasue it will become very thick. At the beginning your soap will be very liquefied and at the end you should be able to mix it like you would honey not water.

Once all of your soap mixture is a thick consistency then you are ready for the final steps of the soap making process.

Step 7: Cleaning Up

The fun time of every lab is to clean up. The main important steps will be highlighted in a numbered list

  1. Make sure to pour vinegar anywhere lye has touched or was inside. Vinegar makes the solution neutral and then it can be poured down the drain
  2. Make sure to use soap to clean all fats (hey we learned how that works!)
  3. Store the equipment for the next time you would like to make soap
  4. All done !!!

Hopefully it wasn't to painful to clean and now you are ready for you soap to finish on up.

Step 8: Soap Molds, Ph Testing, and Additional Adjuncts

Now that your soap is heated to the final stage you can now add any essential oils or leaves or peels to your soap. This will make the soap smell good have a rough texture to clean better, maybe make it last longer. The add-ons and limitless.

For my soap I added green color dye and fir needle essential oil with a small amount of orange peels. With this mixture now smelling and looking great you can pour it into the mold you would like. Anything that is non-stick like an ice tray can work. All the way up to a wooden holder to cut the bars perfectly.

You will want to let the soap sit in an open area to dye for 24-48 hours to be safe. It will become hard and like any other bar of soap out there. Before using the soap it is a good idea to buy a pack of ph test stripes to make sure the soap will not burn you.

Place a small amount of the soap in water and shake it to dissolve the soap. Then go ahead and stick the ph strip into the mixture and see what the ph comes out as, Anything between the ranges of 7-9 ph is a safe bet.

You are ready to use your soap!! Enjoy it and stay clean!!

Step 9: My Soap and How Well Did This Work

Well I have been explain how to make soap and the science behind it. The real question is how did my soap turn out though. My soap was made out of olive oil and lard with fir needle and orange peels added at the end. I had to let it sit for a long time becasue when we pulled it off of the heat it was still very watery. The mold did not work for the soap becasue of this fact.

The ratio of lard to olive oil in my recipe definitely held back the potential that the soap had. If we would have reversed the ratio of fats I think that the olive oil would have been a better base fat for the whole soap to work off of.

In uses my soap did not work your hands became dye but at the same time they also had oils on them. Compared to a commercial companies soap I would put my soap at a .5 out of 10 on their scale. The reason I think that my soap turned out this way is because of the fact that the mixing process was not done yet. It became separated in the container I held it in so the oil went out and the lye went to the top.

Compared to the rest of the class we were not alone. Other groups like mine had the same problem with the same ingredients so it may have just been a time constraint. Some of the groups that used coconut oil seemed to be more successful in there soap creation. I believe that, that type of oil was definitely better when we were on a time line.

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    2 Discussions


    4 years ago

    I think this is ON POINT. duh.