Li Xiuning and Li Feier had never learned common sense of chemistry. They were surprised by the first time they saw strange chemical reactions. Li Yu was not surprised at all. What surprised Li Yu was that what they said was so naive.

Li Yu said patiently: "This is chemistry knowledge, and there are such books in my bookcase. In the future, you can also read and learn about chemistry well. You will understand the reasons. In addition, don't treat these as magical means, it's just a natural reaction of chemistry."

Li Yu paused at this point and said again: "In fact, chemical reactions only transform one substance or several substances into another substance that seems to be unrelated, and you will understand what chemistry is."

This explanation is accurate and easy to understand, and is suitable for those who have never been exposed to chemistry knowledge.

"Oh! So that's how it is, it's really amazing!" Li Xiuning exclaimed.

"So! Don't think that after reading a few books of sages, you feel that you can govern the world. In fact, it's still far from governing the world well." Li Yu said very well.

Li Xiuning opened his mouth to defend something, but was interrupted by Li Yu and refuted: "Reading the books of sages, you can know how salt is made, how wounds are stitched, do you know how big the earth is? Do you know how many continents and oceans are there in this world?"

Li Yu continued without pause and said again: "Reading a book can only mean that you have known words and allusions. What do you know about other natural common sense? But now I will tell you that you probably don't understand. When I teach you my class well in the future, you will understand that the scientific knowledge in the world is so incredible."

After listening to the two girls, they did not answer the conversation. They didn't understand what Li Yu said yet, but they were still full of yearning for the new knowledge they could learn in the future.

Now they didn't care about what happened in the future and were curiously watching Li Yu stir the water in the pot. Under Li Yu's stirring, the lime in the pot was more and more effective, and calcium carbonate precipitated more and more.

Li Yu took a clay pot, poured the clarified liquid on it into the clay pot, then poured out all the sediment below, and cleaned the pot with clean water.

"This is not water, this is a solution of hot alkali. You just need to evaporate the water inside to get hot alkali. Sodium is sodium hydroxide, also known as caustic soda, flake alkali, and caustic soda, and has a wide range of uses." Li Yu didn't care whether they could understand the chemical vocabulary of later generations or not, just let them listen to it.

Li Xiuning and Li Feier listened to these words that they had never heard before. Apart from being surprised, the two women stretched their necks to look at the clear solution. Li Xiuning asked in doubt: "Isn't this water? What else can I have?"

Li Yu smiled faintly and explained patiently: "Fastlime reacts with water, forming ripe lime, that is, calcium hydroxide. Quicklime reacts with sodium carbonate, forming precipitate of sodium hydroxide and calcium carbonate. The sodium hydroxide is dissolved in water, and once the water is heated and evaporated, you can get the hot alkali."

This is a junior high school chemistry course, and even if you close your eyes, you won't make any mistakes. Moreover, Li Yu's current soul is strong now, and the knowledge he learned before seems to be engraved in his brain. Due to his strong strength, his senses have now been strengthened more than tens of times, and his brain's calculation speed is hundreds of times faster. The words and actions of everyone nearby cannot escape his eyes and ears, and then all the information is processed instantly by the brain. This is still the case without using the spiritual consciousness, otherwise it can appear in his brain within a range of thousands of miles.

Li Yu put the pottery jar on the fire and cooked it again, "You will see the hot alkali after a while."

Li Yu took advantage of his spare time to cut the lard into small pieces and then spread the soap mold.

The three of them then went to see the hot alkali and found that the water had evaporated and the white crystals appeared in the clay pot.

"What is this?" Li Feier felt strange, so she stretched out her index finger with her right hand, wanting to touch it and see what it was.

Li Yu hurriedly opened her hand and reminded her: "Fei'er! Don't touch some things you don't understand? This thing is very corrosive and will burn your hands."

After Li Yu reminded him, he wiped the waste cloth on the hot alkali for a few times, and they watched helplessly as the waste cloth slowly turned rotten.

Li Feier was secretly shocked. She didn't expect that this inconspicuous crystal was so powerful. Fortunately, she didn't touch it with her hands, otherwise the consequences would be unpredictable.

In ancient times, whether east or west, the earliest washing ingredients were sodium carbonate and potassium carbonate. The former was a natural lake mineral product, while the latter was the main washing ingredients of wood ash.

In ancient China, three types of detergents were mainly used in laundry washing, one was wood ash. The main component of wood ash was potassium carbonate, which had chemical properties similar to soda ash. It was a commonly used detergent for common people to wash clothes. Of course, soda ash can also be used, but the amount must be controlled well, otherwise a piece of clothing will corrode and rot if it cannot be washed a few times.

The popular detergent is the soap beans formed on the soap bean trees, which is the main raw material for detergent used in ancient times. As Chinese people, they all know that the Yellow River is the mother river. The Chinese nation developed from the Central Plains region and gradually developed from north to south to the Yangtze River region. Now the prosperous Jiangnan region was in the Shang and Zhou dynasties and was occupied by the Dongyi. During that period, people in China regarded these areas as wild lands. Later, the population increased dramatically and the area of ​​arable land decreased, so they launched a large-scale expansion of territory in the Jiangnan region.

When our ancestors were in the Central Plains, they used soapcorns to wash clothes. Later, when we arrived south of the Yangtze River, there were no soapcorn trees, the problem arose. Life still had to be passed. Don’t you wash clothes? They could only find detergents that could replace soapcorns. God pays off. Finally, a tree was found south of the Yangtze River. The fruits on the trees can cure diseases. At the same time, they found that they had the same effect as soapcorns, and they could also be used to clean clothes. The detergent ability was quite good.

So people named the soap tree and the fruit was named soap fruit. Later, artificial detergent appeared, and this name is still used today. To this day, we humans are still using soap to clean clothes. This is the origin of the word "soap".

Another legend is that in the ancient Egyptian palace, a chef named Phoenician accidentally knocked a can of cooking oil underground. He was very scared and quickly scattered the wood ash from the stove on it when others had not discovered it, and then took out the wood ash mixed with oil soaked in his hands and threw it away.

After all this last night, he looked at his hands full of greasy greasy, and thought: I don’t know when to wash such dirty hands until they can be washed! When he put his hands in the water, a miracle happened: he just rubbed them lightly for a few times, and the greasy greasy hand was easily washed away. Even the old dirt that had been difficult to wash away was washed away... and then he invented the soap.

The high-end detergent is pancreatic sap. People in the Wei and Jin Dynasties washed the pig's pancreas/glands, tear off the fat and grind it into a paste, then added bean powder, spices, etc., mixed evenly, and then dried naturally to form pancreatic sap that can be used for washing.

Since it is difficult to obtain large quantities of pig pancreas/glands, the raw materials are very complicated, and the cost is very high, and it is difficult to popularize in large quantities. It is a luxury product. Only those princes and nobles and royal members can afford it.

The lowest end is the wood ash, and there is no need to spend money. Who doesn’t cook at home and doesn’t have to order grass ash?

When Li Yu saw that the lard in the pot had completely melted, he filtered out all the lard residue with a linen cloth, threw the turtle in, and started stirring for a few times to melt the turtle.

After reading it, Li Fei'er was surprised and said, "Why is there less oil in the brother pot? There was obviously a lot of oil just now, why did it disappear all of a sudden?"

After Li Fei'er reminded her, Li Xiuning also discovered the changes, which surprised her. She felt amazing about the things she didn't understand.

"Where did all that oil go?" Li Xiuning asked strangely, looked straight at Li Yu, waiting for him to explain.

"Don't be surprised that the oil has already undergone saponification when it encounters turtle alkali, and now it is dissolved in water."

Li Yu gave them an example again while looking at the ratio of hot alkali: "When we wash clothes, if there is oil stain on the clothes, can't we wash them off with ash? In fact, the ash also contains alkali, but it is not as alkaline as it is."

The second woman looked at Li Yu and then the grease in the pot was gradually disappearing, and did not ask what saponification reaction was. Apart from being surprised, she felt that these chemical knowledge was really magical.

They looked at the oil disappearing from the pot with a look of surprise on their faces: "Well! This saponification reaction is so strange."

Why is it strange? You ask them that they definitely don’t know, but they just feel it’s amazing and just talk nonsense.

Li Yu added the turtle and the others saw that the lard that originally floated on the water had now completely disappeared.

"This step is called saponification. Put the oil and alkali together to heat it to make it produce a chemical reaction. The next thing is very simple, just heat it and make the saponification reaction more fully." Li Yu explained again.

What is soap? The two girls have never seen it before. They only know that it can be used to clean clothes and clean the body. It is similar to pancreatic sap, which is artificial pancreatic sap.

After Li Yu grabbed a handful of salt and sprinkled it into the pot.

The two women who were watching the changes in the pot instantly opened their eyes and their mouths wide open, and they became surprised again.
Chapter completed!