Chapter 353: show you

   Chapter 353 Show you

  The evaporation crystallization method is naturally a method of obtaining saltpeter by boiling or drying it after dissolving it in water.

  Cooling crystallization method, his family Yuebao also said that the solubility of saltpeter in water will decrease with the temperature of the water, and the solubility will become smaller, and finally the solubility is so small that crystals are precipitated, that is, saltpeter is precipitated.

It is all frozen, the temperature must be very low, then even if the saltpeter added in water will not be all precipitated, most of it will be precipitated on the surface of the ice, and then the surface of the ice in the large basin will be directly The saltpeter crystals can be scraped off and reused.

   As for the small part of the saltpeter still in the ice, you can wait for the ice to melt, or boil it or dry it in the sun, and then get this part of the saltpeter.

But in order to prevent their fourth brother from not understanding, and to prevent their fourth brother from finding out that something was wrong, he just said that, as long as the fourth brother knows that saltpeter can be reused, as for other things, when it freezes, saltpeter crystals will precipitate out. , the fourth brother will naturally know.

   At that time, the fourth brother at most thought that his guess was wrong in some places, and he had never touched saltpeter before, so it was only reasonable to have wrong guesses.

   If you guessed it all right, it's not bad at all. With the shrewdness of the fourth brother, you will definitely find something wrong.

   "Can it be reused?!" Xue Sihu rubbed his hands together and his eyes brightened, thinking it was a business opportunity. "That's even better! Then our family only needs to buy saltpeter once! Hurry up, we'll collect it soon, and go to Yuxuan's medical clinic."

   closed the booth, and the things that could be put in the backyard of Shen's Medical Center were put in the backyard of Shen's Medical Center. Then, I came to the front to find old doctor Shen.

  Old Doctor Shen heard that they wanted saltpeter, so he stroked his beard and smiled: "I still have a pound of saltpeter in this hospital, you can take it all if you want."

   Xue Sihu didn't even need to ask Xue Yan, he knew that this pound was definitely not enough, but Xue Sihu couldn't estimate how much, so he looked at Xue Yan.

  Xue Yan glanced at Jiang Yue without a trace.

  To think that saltpeter can be made into ice, a large amount of saltpeter is needed. A small or insufficient amount of saltpeter cannot make water freeze at all. This is why saltpeter has been discovered for so long, and no one has discovered that saltpeter can make ice.

  Jiang Yue scratched her head with her little hand, and compared her without a trace.

  Xue Yan understood, and then handed over to the old doctor Shen: "One catty is not enough, it is estimated that it will cost two hundred catties."

  The old doctor Shen was frightened, and he stopped stroking his beard. After a long silence, he asked, "What do you want so much saltpeter for?"

   He has been a doctor for so many years, and the total amount of saltpeter in the hospital is only four kilograms, and now there is still one kilogram.

   And this saltpeter is poisonous.

  Xue Yan saw that there were no outsiders, and he knew very well what Dr. Shen was like, so he didn't hide it: "Ice making." Then he told what he had read in a miscellaneous journal.

  The old doctor Shen twiddled his beard again, and said with a smile, "It is possible to make ice. Well, I'll show you, and I'll give you two hundred pounds as much as possible."

   He never got it before, he just bought it when he pressed the herbs. He still has some connections in this area, so it shouldn't be too difficult to get 200 jins.

  Xue Sihu hurriedly thanked: "Doctor Shen, I really don't know how to thank you."

   "Thank you, I'm not an outsider." Old Doctor Shen said with a smile. "However, let's talk about it first, I'm going to make ice later, but don't forget me, the old man and our family Yuxuan. My family Yuxuan and I haven't eaten ice yet in the summer."

   (end of this chapter)