At a loss, a bald head wearing glasses appeared at the door of the classroom.

Holding a large wooden box.

The wooden box contains a variety of glassware.

"Is it Class 6?" the man asked.

No one answered, so the bald head hurried to the other floors.

After another five minutes, he followed Teacher Guan back, and his whole expression looked very interesting.

"Hello, I'm your chemistry teacher. The bald head said with a smile.

Then, write two words on the blackboard, "Jiang Wei".

Naturally, as a fan of the Three Kingdoms, I still remember these two words vividly.

After all, "Tianshui praises handsomeness, and Liangzhou produces talents." "If it weren't for Jiang Wei, then the unification of Wei might have been decades earlier.

Therefore, in the Three Kingdoms, Jiang Wei still belonged to the key figure in the late Shu Han period.

However, it seems that with the completion of Cao Ei's series of reforms, the national strength of Wei and Shu has gradually expanded, so even if Jiang Wei is as smart as Jiang Wei tries his best, it is difficult to make substantial gains.

can only watch the Shu State gradually weaken, and there is no successor in the army.

At this moment, Teacher Jiang's voice came, interrupting Wu Zhen's fugue.

"Well, I'm sure everyone is familiar with my name. Teacher Jiang said with a smile.

"That's right, I have the same name and surname as Jiang Wei, the general of Shu during the Three Kingdoms period. Of course, I'm not from Tianshui and don't know how to fight. However, as long as you follow me, then you will be satisfied with the chemistry entrance examination. Teacher Jiang continued.

Then, I started to take out the glass bottle or something, and began to prepare for some experiments.

Naturally, everyone seems to be interested in experiments, after all, in this era, it is not easy to see an experiment.

Wu Zhenzhen couldn't think of any experiments he did himself, but he could only think of the scene of playing with a microscope in the interest class of elementary school.

Then, I saw Mr. Jiang pour dozens of milliliters of liquid into a 250ml Erlenmeyer flask.

"By the way, is there any hand sanitizer here?" Mr. Jiang suddenly asked.

"There is one over the toilet. Chen Quan received it immediately.

Then everyone laughed.

"Okay, you get this beaker and squeeze some of it. Teacher Jiang pointed to a 50ml beaker in front of him and said.

So, Chen Quan took the beaker and squeezed the hand sanitizer.

And Mr. Jiang shook a bottle of dark purple solution there.

Looking at the bottle carefully, it seemed to be very similar to iodine wine in Wu's real impression, but it was different.

Then, Mr. Jiang smiled and said, "Okay, ready." Then, when the student brought the hand sanitizer, our trial began. ”

After a pause, Mr. Jiang smiled and said, "Keep your eyes open." ”

Two minutes later, Chen Quan walked into the classroom with a 50ml beaker full of hand sanitizer.

Then, after taking the bottle, Mr. Jiang used his other hand to make a quiet symbol.

Naturally, everyone's eyes turned to the Erlenmeyer flask in the middle.

Teacher Jiang unhurriedly poured the hand sanitizer into the Erlenmeyer flask, and then the purple-black solution was served.

Teacher Jiang smiled mysteriously and said, "The show has begun." ”

Then, Mr. Jiang poured a little purple-black solution into it.

However, there does not seem to be any noticeable phenomenon.

I only saw that the Erlenmeyer flask was constantly producing bubbles.

Teacher Jiang smiled and said, "What is the phenomenon of this experiment? ”

Yuan Li raised his hand and said, "It's constantly producing bubbles." ”

Su Ye raised his hand and said, "The bubbles piled up, but they quickly collapsed again." ”

Sun Can raised his hand and said, "The purple-black solution added is gone, but the white foam seems to have a little yellow on it." ”

After some discussion, the students came to the conclusion that air bubbles were constantly being generated and accumulated in the Erlenmeyer flask.

As the conclusion was reached, the reaction in the Erlenmeyer flask seemed to quiet down, and gradually, the bubbles built up more and more slowly, so that not many bubbles were produced until the end.

Then, Mr. Jiang smiled and said, "Next, I'll do it again, and everyone will see what the difference is." ”

So, everyone stopped the noise for a while.

Naturally, Chen Quan went to get hand sanitizer again.

It's just that this time, Mr. Jiang has an extra amount of requirements - 50ml of hand sanitizer. In other words, the amount of hand sanitizer should be exactly the same as the 50ml position.

Then, for the weighing of the clear solution, Mr. Jiang also used a strange tube of 50ml.

After Mr. Jiang's explanation, everyone knew that this is called a pipette, which can accurately transfer a small amount of liquid.

Although, the appearance of a red rubber ball squeezed on it seems to be full of fun.

However, Mr. Jiang was very serious when he was doing this.

After moving a certain amount of test liquid to the Erlenmeyer flask, Mr. Jiang said solemnly: "Attention, you must be careful when pipetting. Because this liquid that requires precise access can sometimes be very dangerous, it is important to concentrate. ”

After completing these operations, Chen Quan also filled 50ml of hand sanitizer.

Then, Mr. Jiang mixed the hand sanitizer with the clear liquid in front of him again in the Erlenmeyer flask.

After completing this, Mr. Guan asked, "Next, I want to take the purple-black liquid, can I share the pipette with the clear liquid before?"

Then, the people in the class became two factions.

Naturally, Yuan Li thinks that it is just a matter of taking a liquid, and there is no need to change the pipette.

After Yuan Li put forward his opinion, Wu Zhenzhen immediately stood up and said: "This kind of test is not rigorous. A different pipette should be used. ”

Yuan Li was speechless all of a sudden.

However, Mr. Jiang immediately asked, "Well, it seems that your words are very reasonable. But what if there's only one pipette?"

Yuan Li immediately said, "Yes, what if there is only one pipette?"

Naturally, this seems to be a bit of a pitfall, and it seems that when there is only one pipette, there is nothing to be done.

After thinking about it, Wu Zhen found that it seemed that it was really difficult to answer.

However, the raindrops outside the window suddenly reminded Wu Zhenzhen.

Then, Wu Zhenzhen smiled and said, "Well, if you really want to share it, you have to clean the pipette first." After all, a test with a poor pipette can be problematic. ”

Yuan Ligang was about to refute.

Unexpectedly, Mr. Jiang immediately pushed his glasses and said with a smile, "Good, good, good." With this mindset, you will definitely be able to learn chemistry well. ”

After a pause, Mr. Jiang continued: "Everyone take a closer look at my following operations. ”

It seems that this purple-black liquid requires very little, so the pipette selected by Mr. Jiang is very delicate and disproportionate to the red rubber ball on it.

When using this pipette, Mr. Jiang seemed to be oozing some beads of sweat.

It seems that every time the red rubber ball is tightened and relaxed, it is difficult to get to the desired position.

Looking at this situation, Wu Zhen understood that the first test he did was likely to be flawed.