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Introduction of high-frequency articles in senior high school chemistry

This paper makes statistics and analysis on the real questions of chemistry interviews in senior high schools in recent years. Some contents of high school chemistry frequently appear in teacher interviews. This paper lists and summarizes the import cases of high-frequency chemistry interview content in senior high school, so that candidates can choose appropriate import methods and materials in the interview, or give inspiration and enlightenment. Examples of high-frequency content introduction in senior high school chemistry interview;

1. redox reaction

Example ①

Review and recall the common oxidation and reduction reactions in chemistry study and life, and write the reaction equation.

What are the common characteristics of these responses to the introduction of new courses? These reactions are all redox reactions. So what is redox reaction? In this lesson, we will learn about redox reaction together.

Example ②

Create situations and ask questions. After the peeled apple is left in the air for a period of time, the surface of the apple will turn brown. But the apple juice on the market does not change color. Why? It is suggested that vitamin C in apple juice can prevent the discoloration of apple juice.

In air, Fe2+ in apples is oxidized to Fe3+, which makes apples discolored. Vc added in apple juice reduces Fe3+ to Fe2+ to prevent discoloration. These chemical changes are what we are going to learn in this class-redox reaction.

2. Periodic law of elements

Example ①

Review the elemental properties and atomic structure of alkali metal elements and halogen elements.

In the previous course, we have studied alkali metal elements and halogen elements, and we know that different alkali metal elements and halogen elements have certain similarities and gradualities in structure and properties. Are there any rules for other elements in the periodic table? In order to better understand the properties of elements in the periodic table, we will discuss the periodic law of elements in this lesson.

Example ②

Multimedia shows the most common laws of calendar and moon phases in life.

The introduction of the new curriculum is rain or shine, and as time goes by, these facts show a periodic change law. We have studied the periodic table of elements, so does the periodic table have periodic changes? In this lesson, we will learn the periodic law of elements.

3. Ion reaction

Example ①

Multimedia display of several sports beverage labels.

Most of the labels of the new courses are marked with "electrolyte drinks", which can quickly replenish the water and electrolyte lost in human activities. What is electrolyte? You can know the answer through today's learning content-ionization of acid, alkali and salt in aqueous solution.

Example ②

By studying the classification of substances, we know that compounds can be divided into acids, bases, salts and oxides according to their properties and compositions. But the classification standards are different, and the classification results will be different. Can compounds be classified according to other standards? Today we will learn the main content of this lesson-ionization of acid, alkali and salt in aqueous solution, and learn another classification method of compounds.

4. Chemical reaction rate

Example ①

Play video explosion, cave formation, rust, milk deterioration.

We can see from the video that the speed of different chemical reactions is different, and the speed of describing reactions for different reference objects is also different. Therefore, it is necessary to quantitatively describe the speed of chemical reaction. In physics, the speed of an object is expressed by the distance it moves per unit time, so how to quantitatively express the speed of a chemical reaction in chemistry? This is the chemical reaction rate we are going to learn today.

Example ②

Multimedia display of bread label (carefully check the shelf life description of bread).

The shelf life of bread is different at different temperatures. How does temperature affect the speed of chemical reaction? Besides temperature, what other factors will affect the speed of chemical reaction? In this class, we will explore the factors that affect the rate of chemical reaction.

5. Chemical bonds

Example ①

Create a situation where two magnets are close together, and they will only be attracted by magnetic force; Human beings can live safely on the earth because the earth has gravity on human beings.

Introduce a new lesson: What are the ions that make up matter in the microscopic world? Today, we will learn about this "force" in the formation of chemical substances-chemical bonds.

Example ②

By displaying pictures, scientific information can distinguish the microscopic images of chemical bonds in "graphene molecules" and "C60 single molecules". It is reported that "Swiss researchers used atomic force microscope to capture high-definition microscopic images of chemical bonds of graphene molecules" and "China researchers used scanning tunneling microscope to capture carbon 60 single molecule images that can distinguish chemical bonds for the first time."

The world introduced by the new curriculum is made up of matter, which is made up of particles such as molecules and atoms, and particles form matter through chemical bonds. Through the high-definition microscopic images of chemical bonds, people can understand the true face of chemical bonds, so what is chemical bonds? Today we will learn about chemical bonds together.

6. Acetic acid

Example ①

Creating a situation We often add vinegar and cooking wine in the process of cooking fish, which makes the fish odorless and delicious.

Why can you make delicious dishes by adding vinegar and wine? We will know the answer through today's study. The main component of vinegar is acetic acid. In this lesson, we will learn about acetic acid, a common substance in life. Its chemical name is acetic acid.

Example ②

Citing the story of the Origin of Vinegar, Heita, the son of Du Kang, the wine saint, found that more and more distiller's grains could not be treated during brewing. After thinking hard, he put them in the wine container "You", added some water, and finally sealed the mouth of "You". After many days, Heita inadvertently remembered, opened the vessel and smelled the fragrance. Distiller's grains were put into "Unitary" for exactly twenty-one days. "Twenty-one days" together, "yesterday" is the word "vinegar". So this sour liquid is called "vinegar". Heita accidentally brewed a condiment-vinegar, which Du Kang and his son gave to their neighbors to taste.