The whole place was silent. Everyone looked at Li Zhen in stunned silence, and then at Qi Denming, who was blushing and thick-necked.
This... this is amazing.
This hot ice phenomenon is inherently magical. Unexpectedly, Li Zhen was able to tell the truth. What else did he not know
Li Zhen continued: "The so-called hot ice phenomenon is actually not ice. It is a supersaturated sodium acetate solution. After being stimulated by certain stimuli, excessive solutes will form rhombus crystals from top to bottom. It looks like ice, but in fact Crystals radiate heat, so they are called hot ice.
Supersaturated sodium acetate solution looks like water, but is actually not water. Its interior is in a metastable state. If the solution is contaminated with sodium acetate trihydrate crystals, this balance will be disrupted, triggering rapid crystallization of the solute. When sodium acetate crystals are put into the supersaturated solution, the crystals will become 'seed crystals' and thus act as a medium, guiding the process of breaking the supersaturated equilibrium and reducing everything to crystallization. This is not a water-to-ice experiment, but an experiment in which a supersaturated solution of sodium acetate is reduced to sodium acetate crystals. "
Qi Denming was stunned at this time and couldn't say a word. He was extremely embarrassed.
At this time, a chemistry teacher raised a question: "Li Zhen, I don't agree with your statement. Sodium acetate is widely used, so we have many experiments on sodium acetate. You said this is a solution of sodium acetate, but In the past, we also mixed sodium acetate crystals with water, but why didn’t they crystallize at that time?”
Li Zhen smiled and said: "Teacher, if sodium acetate and water are mixed together to form a supersaturated solution, then this is too simple."
The teacher asked: "Then why didn't we discover it before? Why can it crystallize now?"
Li Zhen said: "Because you want to crystallize sodium acetate, there are some steps. The first step is to mix sodium acetate and water at a ratio of 1.3:1. Sodium acetate dissolves in water. Then the solution is heated to boiling state, about 80-95 degrees. Continue stirring during the heating process until the sodium acetate crystals completely merge with the water. Only after a thin film forms on the surface of the heated sodium acetate solution can it be allowed to cool. Call it a supersaturated solution of sodium acetate.”
Everyone turned to look at Qi Denming and asked:
"Is that so?"
"Do you really need to heat it up?"
"Heating and stirring?"
“…”
Qi Denming smiled bitterly, cupped his fists and bowed to Li Zhen: "Master Li!"
'Wow—'
The crowd was in commotion, it was true.
Qi Denming then said: "Yes, when I was doing the experiment, I had a sudden idea of what would happen if the sodium acetate solution was boiled. Then I heated the solution and brought it to a boil. I cooled the boiled solution Finally, I wanted to move it to another place. But my hands shook, and the solution accidentally spilled on the sodium acetate crystals on the table. The water that was spilled at that time, oh no, was a supersaturated solution. It condensed on the table on the spot. It's frozen... It was by chance that I discovered such a phenomenon.
I originally wanted to use this phenomenon to challenge Master Li's knowledge. I also wanted to draw everyone's attention and announce this phenomenon. But I didn't expect... Master Li has an insight into everything. I didn't understand the phenomenon that I discovered by chance, but he was able to explain it in one sentence. admire. "
With that said, Qi Denming bowed to Li Zhen again.
Everyone couldn't help but get goosebumps and were filled with emotion.
Science, what is science
Isn't it just the result of accidental trial and error
Qi Dengming is representative of sudden whims and accidental discoveries.
Accidentally, my hand shook and the solution spilled out. Accidentally, it spilled onto the table with crystals stuck on it. Accidentally, the phenomenon of hot ice was achieved.
Science is the accidents that keep appearing in the process of constant trial and error.
Li Zhen also bowed to Qi Denming: "Senior Qi's ability to discover this phenomenon is God's blessing. We should respect everyone who has science in mind. I also admire Senior Qi's bold hypothesis and spirit of trial and error."
Qi Denming smiled bitterly, feeling so moved that he didn't know what to say for a moment.
In the silence, Xu Shenxue suddenly spoke: "Li Zhen. You just said that there are other ways to freeze water? Or is it real ice?"
As soon as these words came out, the scene became even quieter. Everyone turned to look at Li Zhen again, eyes full of expectation.
Li Zhen nodded: "Yes. There are many ways to freeze water."
Xu Shenxue came over and said excitedly: "Hurry up and tell me."
Li Zhen never concealed anything from other people's questions, and said it bluntly: "There are also ammonium nitrate icing, calcium nitrate, and ammonium chloride icing methods."
"There are so many ways to freeze?"
"Is this true?"
"What is ammonium nitrate?"
"Water doesn't have to wait until winter to freeze. So it can be frozen artificially?"
"That person is too outrageous. This is an act that goes against heaven."
“…”
Li Zhen said calmly: "If you want to freeze water, you need to know the characteristics of water. When water is under 1 standard atmosphere and below 0 degrees, it will reach the freezing point. In the water at the freezing point, there is a The molecules produce crystals, which can be called 'seed crystals', and then become media, quickly infecting other water molecules of the same temperature, thus forming a large area of ice. This is one of the three forms of water: steam, water, and ice. , properties of ice.”
A chemistry teacher stood up, trembling with excitement: "Then what? Then how to freeze?"
"Take ammonium nitrate as an example. The characteristics of ammonium nitrate are: water absorption, agglomeration, and heat absorption. When boiling water to form ice, we take the heat absorption characteristics of ammonium nitrate. You can use a large basin... In this way, in the laboratory Is there any ammonium nitrate? I will test it on site."
"What is ammonium nitrate?"
a chemistry teacher asked weakly.
Li Zhen slapped his forehead and forgot about it. Fuxing University currently does not have the ability to prepare ammonium nitrate. Otherwise, the main structure of ammonium nitrate contains ammonia gas, and ammonia needs to be prepared under high pressure and high heat. Fuxing University currently does not have equipment that can achieve high pressure. Later, there was no technology to extract ammonia, because ammonia is highly toxic and difficult to extract.
"In that case, we will use saltpeter instead of ammonium nitrate. At a certain temperature, saltpeter can also have a certain probability of freezing water."
After hearing what Li Zhen said, Xu Shenxue jumped to his feet quickly: "Quick, find saltpeter!"
"Saltpeter."
"Hurry up, go get the saltpeter."
“…”
One by one, the classmates who were standing behind and watching the excitement ran out, looking for saltpeter everywhere. Everyone’s enthusiasm for science is extremely high.
Within ten minutes, someone brought what Li Zhen wanted to use.
A large basin, a bag of saltpeter, and a beaker.
Li Zhen first filled a large basin with water, then poured all the saltpeter into the basin, and handed a wooden stick to Qi Denming: "Stirring the water and saltpeter will fully absorb the heat in the water."
Qi Denming was shocked and said: "This...could it be that if you stir like this, this basin will freeze?"
Li Zhen smiled: "Of course not."
Turning to look at his classmates: "I need a cup of water from a deep well. Nowadays, the water at room temperature outdoors has a higher temperature due to the weather, and it takes a long time to achieve the effect. The water in the deep well loses heat. There are more, and the water temperature is lower, which is more suitable for completing this test quickly.”
"Go, get water from the well!"
"I want the coldest well water!"
“…”
Some students ran to the well in groups on the spot.
"Want the coldest well water?"
"In fact, the water closer to the bottom of the well is icier. The water temperature on the surface of the well is relatively high due to the weather."
"In this way, you hang me down, and I will drill down to the bottom of the well to get the deep well water."
"be safe,"
One classmate took off his shirt on the spot, tied a rope around his waist, and slowly climbed down with a bottle with a cap in his hand.
'Plop' jumped into the narrow well and dived in. Go to the bottom of the deepest well.
The surroundings were surrounded by classmates, all talking about Li Zhen.
After waiting for about two minutes, there was no movement in the well. A classmate shined a flashlight down, but it was silent.
"classmate!"
"Quick, pull it out!"
"Get him out quickly."
"This well is very deep. People have drowned before. Don't let any accident happen. :"
"No, the rope is broken!"
"Ah! Call for help quickly."
"What should I do? What should I do?"
“…”
Just as everyone was in shock, there was a 'pop' sound and there was movement in the well.
Everyone hurriedly lay down and looked inside, only to see the shirtless classmate's face was covered with water, and he was panting heavily. Seeing everyone at the entrance of the well looking at him with concern, he chuckled and proudly raised the bottle with the cap tightly in his hand:
"I got it, it's very cold!"
"Pull me up quickly and send the cold water over, otherwise the ice water will be destroyed by the room temperature. I want to see the experiment."
“…”
Everyone looked at the classmate at the bottom of the well who was climbing up and down with a silly smile, and there was silence.
(End of chapter)