How to get a trick to the chemical formula of junior high school chemistry

The chemical formula is not memorized, but combined with valence, if you want to learn all the chemical formulas in junior high school, you might as well memorize the valency formula, right? If you memorize it, there will be a lot of high school out, what are you going to do? Do you want to memorize it? I have one here that is more practical and easy to memorize:

N-1 potassium, sodium, silver and hydrogen, n-dicalcium, magnesium, copper, barium, zinc. Positive three aluminum, positive four silicon, one or two copper, two three iron (common price change).

Negative fluorochlorobromine and iodine, negative dioxide, sulfur, trinitrogen, phosphorus, chlorine are found in 157, 2467 manganese is just right, many elements have valence, and the conditions are different.

Negative hydroxide mononitrate, negative disulfite carbonate, positive monovalent ammonium.

In other books, the valency formulas are very cumbersome, such as chlorate and permanganate are not used at all, so according to my memorization, they are all clear, and there is no need to remember the compound, and you can write it down by saying the name.

Chemistry is not politics, although I also memorize it, but there are skills in it, I hope mine will help you!

When you have nothing to do, go to the bookstore to buy a full explanation of the textbook for middle school students or study handouts, which have a lot of rules and tips in advance, and it is very useful to read carefully and do it against the example questions. I hope it will be helpful to you, I think you will definitely be interested in chemistry after reading it, and you must preview chemistry in advance, and you must remember what the teacher says in each class, especially when you first start learning. In this way, you can learn more and more easily in the future.

Memorize the valencies of common elements, and remember that most compounds have positive valence first and negative valence last.

How to learn chemistry well in junior high school? What are some good ways to learn?

Unexpectedly, the three years of junior high school passed immediately. Looking back. I still miss it.

I sorted out some volumes and some books at home, and there were a lot of them. And the high school entrance examination is not as scary as everyone thinks. It was just a simple exam, and then the three years of junior high school were over.

In the third year of junior high school, how many reference books and how many volumes we turned over. Just for this exam. So, now I'm going to tell the soon-to-be junior high school students how to learn chemistry well.

Experimental setup. Well, let's not say these useless words. Actually, my chemistry level is not very high, but I hope that students who are about to enter the third year of junior high school can also have some of their own learning methods when studying chemistry, I hope it will help you.

First, it is necessary to make the examination of the topic clear.

This sentence seems to be nonsense, but many people know this, but they can't do it. In fact, this is the basis of the question, you have to clarify the conditions given in the question, and then make the answer. In the high school entrance examination, I often feel sad because I didn't get the basic score.

The second is to memorize the law of conservation.

The laws in chemistry tend to look the same and seem to be useless, but they tell you that this is a concept that you have to remember, and that you can use it when you do a math problem. And when writing chemical equations, you must be conserved, otherwise you will be wrong in this question. Therefore, please remember the law of conservation and memorize it to the death.

The third is to find the cause.

The fourth is to read more chemistry books outside of class.

The fifth is to lay a good foundation, which is the foundation of all knowledge.

The foundation is learned from the beginning of junior high school, the foundation is the foundation of all knowledge, it is very important for how to learn junior high school chemistry well, if there is no foundation, you can't improve your grades later, so the foundation is very important. There's not much to say, just be sure to memorize the basics.

Students do experiments.

The sixth is to stick to the experimental problem.

As for the experiment, the first point is to consider the problem of excess, and the second is to consider the gas when inhaling, and after passing through the liquid, a trace amount of liquid will definitely be brought out, such as water. The third is to grasp the reaction phenomenon and so on. The fourth is to be environmentally friendly and efficient, and the fifth is to remove impurities cleanly, and no new impurities can be introduced.

The above is about how to learn some methods of junior high school chemistry, a total of six points, please remember that these are prepared by your predecessors, I hope you can be admitted to your ideal high school!

The biggest feature of chemistry is that the knowledge is fragmented and there are many knowledge points. There are a lot of things that need to be memorized and memorized at the beginning, and with a certain foundation, you can find the rules. For example, start memorizing element symbols (junior high school generally requires the first 20 elements of the periodic table), memorize the symbols of atomic clusters, memorize their common valences, and then learn matter and start memorizing the chemical formula of matter, there is a rule:

Generally, the positive price comes first, the negative price comes last, and the algebraic sum of positive and negative valence is zero. Later, when I learned about chemical reactions, the reactions between substances were also regular: for example, acids and bases reacted to form salts and water, and so on.

Knowledge is accumulated bit by bit, don't be discouraged, calm down, and sort out the things that should be memorized: categorization, such as material color: memory special, solid:

Black: Cuo MnO2 Blue: Cholelum ( Purple Black:

kmno4, others are mostly white solutions: fuchsia: kmno4 light green:

Ferrous chloride, ferrous sulfate Yellow: ferric chloride Ferric sulfate litmus test solution: purple itself (red in acid, blue in alkali) phenolphthalein:

In the process of learning knowledge points like alkali turning red, I wish you more chemical progress (I believe in you, I can succeed).

Be diligent in previewing, be good at listening to lectures, take notes, and try to do an after-class practice.

Review often, memorize more, review in time after class, and do homework carefully.

Thoroughly understand the textbook, connect with the reality, and carefully study the textbook with the textbook as the main line.

Pay attention to experiments, cultivate interest, carefully observe the teacher's demonstration experiments, and prepare two notebooks before learning chemistry.

Some can be remembered according to its reaction principle, for example, the metathesis reaction remembers its conditions (there is no insoluble in the reactants, there is gas, water, gas or precipitated in the products), and the equation of any metathesis reaction can be written according to the valency; Some memorize the state of the equation, like what bubbles are precipitating, etc.; And some are to be memorized, like potassium permanganate to make oxygen, write more and practice more.

Remembering the valence state of the elements, and the conservation of atoms, it is enough to know what the product is, and there is no need to memorize it.

Junior high school, it should be okay. You can remember from the ions, such as what and what will precipitate, what and what will emit gas. That's part of it. The rest has to be memorized by rote. In my memory, there are not many chemical equations in junior high school, which are far worse than those in high school.

Write according to feeling and regularity, don't memorize by rote, read it a few times and memorize it.

1. Listen carefully and take good notes. Good note-taking is the condensation, supplementation and deepening of textbook knowledge, and the presentation and refinement of the thinking process.

Due to the fact that the knowledge points of chemistry are both numerous and fragmented, in addition to listening carefully and thinking positively, in addition to listening carefully and thinking positively, it is also necessary to write down the key points, difficult knowledge, ideas and difficult points of the teacher in their own language on the basis of understanding, so as to facilitate future review.

2. Review in a timely manner. Revision is not just a simple review of knowledge, but considering the interconnection of old and new knowledge in one's own brain, and reorganizing it to form a new body of knowledge.

Therefore, after class, it is necessary to review the content of the lecture in a timely manner, and do a good job of sorting out and summarizing the knowledge, so as to integrate the knowledge and avoid the phenomenon of more and more chaos in learning. For example, if you learn about the bleaching properties of carbon dioxide and chlorine water, you can compare them to find out the differences.