{"id":66672,"date":"2026-08-20T05:26:10","date_gmt":"2026-08-19T20:26:10","guid":{"rendered":"https:\/\/phys-edu.net\/wp\/?p=66672"},"modified":"2026-08-20T05:26:10","modified_gmt":"2026-08-19T20:26:10","slug":"made-from-oil-we-tried-turning-salad-oil-into-homemade-soap-the-chemistry-of-cleaning","status":"publish","type":"post","link":"https:\/\/phys-edu.net\/wp\/?p=66672&lang=en","title":{"rendered":"Made From Oil!? We Tried Turning Salad Oil Into Homemade Soap (The Chemistry of Cleaning)"},"content":{"rendered":"

I’m Ken Kuwako, your Science Trainer. Every day is an experiment.<\/strong><\/span><\/p>\n

Do you know what soap is made from? Believe it or not, it starts with something as familiar as cooking oil. And even more surprisingly, the process involves the very same kind of chemical reaction that helps us clean greasy stains in our everyday lives. This time, I tried making soap with students from our science club, following the soap-making experiment featured on page 196 of the book “Mensoore! Chemistry<\/a>” (Iwanami Junior Shinsho).<\/p>\n

Just Three Ingredients! Making Soap from Cooking Oil<\/h3>\n

All you need is a 2-liter PET bottle designed for carbonated drinks, water, sodium hydroxide, and cooking oil. The process is surprisingly simple.<\/p>\n

First, pour 100 mL of water and 45 g of sodium hydroxide into the PET bottle. There is one very important point to keep in mind here. When sodium hydroxide dissolves in water, it releases a large amount of heat. For this reason, be sure to place the PET bottle in a container filled with water while dissolving the sodium hydroxide completely.<\/p>\n

\"\"<\/p>\n

Once the sodium hydroxide has completely dissolved and the PET bottle has started to cool down, add 330 mL of cooking oil. Used cooking oil works just fine, too. Knowing that oil that would otherwise be thrown away can be transformed into soap makes the whole thing feel like a pretty good deal!<\/p>\n

\"\"<\/p>\n

Tighten the cap securely, and then all you have to do is shake, shake, shake! Aim for about 10 minutes.<\/p>\n

\"\"<\/p>\n

It is quite a workout, but we keep going!<\/p>\n

Once you’re done shaking, pour the mixture into whatever mold you like, such as a milk carton or paper cups, and let it dry for 2\u20133 days. Remove the soap from the mold, cut it into whatever size you like with a knife, and then let it rest for about another month. Your homemade soap is ready!<\/p>\n

The Chemical Reaction Behind Soap Making<\/h3>\n

Now we get to the most fascinating part. Let’s take a closer look at the moment soap is formed using a chemical equation.<\/p>\n

\"\"<\/p>\n

\"\"<\/p>\n

In fact, this reaction works in exactly the same way as the chemistry behind cleaning greasy stains in our everyday lives. The same type of chemical reaction takes place when we use detergent to remove grease from kitchen surfaces. In other words, making soap is essentially a way of deliberately carrying out the chemical reaction that breaks down greasy dirt and capturing the result in the form of “soap.”<\/p>\n

Let’s take a look at the main players in this equation, starting from the left.<\/p>\n