What is the focus of junior high school chemistry? What is the focus of chemistry in junior high sch

Reciting the element symbol, valency, and being able to write chemical formulas according to valency.

It is necessary to understand the properties of matter and be able to apply them to explain the phenomena that arise around us.

Be able to understand chemical reactions correctly and write chemical equations fluently.

Note the comparative induction.

I don't think it's easy to do all of that.

Chemical elements, valency must be able to memorize.

And then there's the solution, the acid, the base, and the salt, which are the most important parts.

But I don't think much will come out of the exam.

In fact, junior high school chemistry is very simple.

The exam will take up to 50% of your books

It is also to lay the foundation for future high school studies.

In fact, junior high school chemistry is very simple, but the foundation must be solid, especially the chemical equations, everyone feels simple, but the exam must be taken, every time someone makes a mistake, you must remember it.

The focus is on 1: the periodic table of chemical elements.

2: Microscopic substances such as atoms and molecules.

3: Acid-base salts and solutions.

The foundation is the most important.

The focus is on the base and acid-base salts.

I don't want to talk about the previous ones, I think experimentation is more important, and now there is more and more emphasis on practical hands-on ability and so on.

Equations and properties of matter.

Back!! There is also understanding, and **, think more about yourself, find more problems, it's better than others asking you questions!!

Acids and bases, molecules, atoms, ions.

The general focus of junior high school chemistry should be as follows:

1.Acids and alkalis.

2.Four types of reactions + the law of conservation of mass.

3.Oxygen, carbon dioxide.

4.The composition of matter.

5.Lab questions.

The first four of them should not be difficult as long as you read the book well and do more questions.

The fifth one can't read the book, so you should do some classic questions and then memorize the answers, because some things are wrong with one word.

Hope it helps.

Acid-base salts, solutions, substance composition.

There are not many things in junior high school chemistry, the focus is on equations, it is best to master them all, you can understand all the equations, know the reason, the principle is very good, because the choice and calculation questions are all around these.

Don't think it's too much, when you get to high school, a lot of things are used, and they are the same, compared to high school or even college chemistry, these equations are simply too few, too simple...

In addition, there are some things in the experiment, which have been too long, and I don't remember it clearly, some operations, pay attention to the problem.

The focus is on the acid-base salts, which is also a slightly more difficult chapter.

There is absolutely no problem for others to follow the teacher

1.the essential difference between chemical and physical changes and some special cases; For example, the light emitting of a light bulb is a physical change, because it does not generate other substances, but only emits light and heat; Fermentation is a chemical change that produces other substances during the fermentation process.

From the above two examples, it can be shown that the essential difference between chemical change and physical change is the formation of new substances.

2.It is necessary to find out the percentage of each gas in the air in the air.

3.Memorize the chemical formula, experimental equipment and experimental procedures of some experiments.

4.Three experiments and chemical formulas for the production of oxygen in the laboratory.

4.In the experiment of electrolysis of water, the conclusions obtained are: water is composed of elements and oxygen, and is composed of water molecules; In chemical change, a molecule is the smallest particle that maintains the chemical properties of a substance, and an atom is the smallest particle that makes up a substance.

But in the case of non-chemical changes, the atoms are divisible.

5.In junior high school chemistry, there are some calculations about chemical formulas, so be sure to remember the chemical formula, relative atomic mass, and valency [Note]: In some large exams, the relative atomic mass that will be encountered in this exam will be given in front of the test paper, so there is no need to deliberately remember it and waste time here; It is important to keep in mind the valency as it is important to write the chemical formula.

6.In the ion section, you must be able to draw a schematic diagram of the ion structure, sorry, I'm now in the third year of junior high school, I just know this Moduo, it should be able to help youA perfect score of 50 in chemistry and about 45 points in the test.

Junior High School Chemistry The main key question types are: experimental questions, inference questions, calculation questions, experimental questions: The main review method is to memorize all the test details and experimental diagrams in the book.

Inference questions: The main review method is to memorize the physical properties (mainly color, fragrance, taste) and chemical properties (mainly chemical equations) of substances mentioned in the third year of junior high school.

Calculation questions: Do the exercises by type, don't do too much, do the questions you have done several times and be familiar with them!