Police Detective

Today's class was a relatively basic class. Bai Song was distracted at first, but after the book was in his hands, he had no other thoughts and listened more seriously.

In the entire classroom, there were only two people who did not listen to the class.

One doesn't need to listen at all, the other doesn't listen.

Bai Song knew what was marked in the book. Although it was just a few strokes for the girl, he would definitely have to analyze it carefully, and it would probably take him two days to read it.

This is the difference between professionals and amateurs.

What level is Bai Song studying in chemistry these days?

If compared to people who are not majoring in chemistry, they still know something. But any chemistry undergraduate who studies well can easily defeat him.

The development of science has been sufficiently segmented that it is no longer possible for any one person to master the knowledge of all industries.

At this time, Professor Tang talked about Le Chatelier's principle.

Everyone here who majors in chemistry knows this principle, and has dabbled in high school chemistry, but no one showed any willingness to hear it.

The theorem is simple: in a reaction that has reached equilibrium, if one of the conditions affecting equilibrium is changed, the equilibrium will move in a direction that weakens the change.

Le Chatelier's principle, Newton's first law and Lenz's law are very similar, they are all laws of inertia.

In other words, inertia exists in chemical reactions, classical mechanics, and electromagnetism. When accelerating, there is "resistance" (that is, inertia) to limit your acceleration, and when you want to decelerate, there is also inertia to limit your deceleration.

Bai Song also has his own explanation for this principle.

For a large-scale project, there will be inertial resistance during the planning stage. The more planning, the greater the effort required. And after the case is over, if you want to stop the case, there will still be inertia that will restrict the termination of the case.

To solve a case, the police must try their best to understand the case in advance while the case is still moving, while the limitations of objective conditions still exist, and before the speed has returned to zero, and then arrest the person.

"After teaching this basic chemical principle, I would like to ask everyone first, how many people have a certain understanding of this principle before attending the lecture?" Professor Tang briefly chatted with everyone.

After Professor Tang finished speaking, almost half of the students raised their hands.

When Professor Tang saw this, he generally understood it, and then asked: "So, now that I have finished speaking, do you have any questions about this principle?"

There was no one to ask the next question.

This is indeed a very basic chemical principle. It is normal for no one to ask questions. Everyone can master this scientific principle.

Professor Tang nodded and then asked: "Students are here. Some are doctoral students in the Department of Chemistry, and some are non-chemistry majors. They are also very interested in chemistry, so I want to have a chat with you first. , what is chemistry? Does anyone want to tell me?"

The class was still very active. Several students stood up to express their opinions. Some just expressed that chemistry is a science, and some mentioned that chemistry is a reaction process that creates new substances. More The person just explained the definition.

The atmosphere in the class was very good. Professor Tang was very happy. Seeing that the students had almost finished chatting, he said, "Maybe many people have heard that I left the school for a while. Outside, I had a bookstall and learned a lot. Many things happened.

In the school, there are outstanding college students like you, and there are also some professors and teachers who have made great achievements in various fields, but after all, they are at the top of the temple.

Some time ago, a woman who was a little older than me came to buy a cookbook from me, and I chatted with her for a while. She mentioned an acid-base food theory, told me that vinegar is an alkaline food, and vowed to share the theory with me.

This makes me feel very interesting. Could it be that chemistry has changed so much since I left school for more than half a year? "

Sparse laughter.

Professor Tang paused for a moment: "Many students didn't laugh. Are they doubting what she said makes sense?

Chemistry is actually a very interesting subject.

When you go to high school, you will find that many things in junior high school are wrong. When you go to college, many of the knowledge points in high school are wrong.

I once read a middle school chemistry book, and there was a chemical substance like nitric tetrahydride in it. Of course, this does not exist now, but it still does not affect middle school students in solving questions.

However, we cannot laugh at the simple knowledge we have learned. As a science, even the first lesson in junior high school has its reason.

We know that all substances, even pure water, are chemicals. We know that matter is composed of atoms, and we also know that matter does not arise out of thin air, let alone disappear out of thin air.

These are all correct. Even in the field of mass-energy conversion, you cannot say that this is wrong.

However, during this time, I discovered a lot of interesting things.

Some people believe that some other metals can catalyze the formation of gold;

Some people believe that water can be catalyzed to generate hydrogen and then enter the hydrogen fuel cell to drive the car forward;

Some people believe that eating a little barbecue can cause cancer;

There are also people who are superstitious about various health products, enzymes and other professional terms.

The most interesting thing is that many of our students will believe some scams after several twists and turns. "

Professor Tang talked a lot and then changed the subject: "So, what is chemistry?

Chemistry is always a rigorous science. When you study it, you can always question it and try to discover new problems. However, you cannot let what you learn not belong to you.

Don't think that this kind of thing will never happen around you. Let me ask, are there any girls here who study biology? "

A dozen girls in the classroom raised their hands.

“So, from a biological perspective, what exactly does a facial mask do to the skin?”

Not a single one of the dozen or so girls spoke.

From a scientific point of view, it is of no use at all! But these girls are using it.

"Then let me ask you again. Many people think that eating pig skin or even isinglass can supplement collagen. Do you think this is correct?"

"Incorrect." A few people finally plucked up the courage to answer.

"Speak louder." Professor Tang approved the answers of several people: "We all study science, so we must believe in science. The human body can never absorb protein directly. No matter what kind of protein it is, it is digested into The polypeptide chain is then broken down into amino acids. Eating those so-called 'high collagen' foods is actually not as good as eating eggs."

In the university classroom, these words, which were almost refuting rumors, made many people think deeply.

After studying for so many years, how could I become stupid?