How to improve physics and chemistry quickly in the third year of junior high school

Do more practice, and practice writing more equations in chemistry.

The methods of improving the physical chemistry of junior high school are as follows:

1. Return to the textbook and review selectively.

Everything is the same, and the use of basic knowledge is also inseparable from difficult topics. In the last three months, students have limited time to revise, so it is important to make a wise choice about revision. Focus on reviewing the content of the syllabus, find out the knowledge points that you don't understand in the syllabus, and then analyze the knowledge points you don't understand until you finally understand it.

For students with a good foundation, they can review their knowledge together, specialize in difficult problems, and strive to make breakthroughs in difficult problems. For students with poor foundation, they must review all the textbook knowledge, focus on the basic questions, and strive to get all the basic questions right, so that the physics score will not get a very bad score.

2. Identify the key and difficult points.

Students will review and assign according to the requirements of the syllabus and the proportion of scores for different question types. Acoustic focus: timbre, tone, and loudness. Optical focus: reflection, refraction, plane mirror principle, lens imaging.

3. Focus on weak knowledge points.

By brushing various exam questions, find out your own error-prone question types, mainly review error-prone knowledge points, sort out various error-prone question types in your notebook, and focus on reviewing these question types.

4. The basic knowledge is sorted out and memorized in the category of laughter.

Proficiency in the names and writing of elements. Important chemical equations must be memorized, and chemical calculation of mass fractions must be learned.

5. Brush the questions. The various knowledge sections of chemistry are relatively scattered, you can do some real questions to find out some problem-solving skills and ideas, and skillfully use various formulas to solve the problems.

Clause.

1. Understand the principle

Chemistry is a science subject, and it is not a subject that can be improved purely by memorization like the liberal arts, and this kind of logical subject must be understood thoroughly. The principle is the most primitive and basic basis for solving problems, and if you master the principle, you can peel off the complex problems and solve them step by step. After all, no matter how complex the problem is, it is inseparable from the theoretical foundation, and the skillful use of the principle is the key to solving the problem and scoring it.

Clause.

2. Pay attention to mistakes

Although junior high school chemistry is only studied for one year, there are relatively few knowledge points, and the types of questions are limited, which highlights how important it is to sort out the wrong questions. Categorize the wrong questions, analyze the wrong questions, find the knowledge points that you don't know, and ensure that the mistakes will be one by one. Sorting out the wrong questions is also one of the most effective and convenient ways to check and fill in the gaps, especially for a highly skilled subject like chemistry, the wrong questions must be paid attention to.

Clause.

3. Summarize and review

In the end, it is a summary and review, and this is also the most indispensable. Listening to lectures and doing questions are both in the process of learning new knowledge, but be sure to stop and summarize. Summarizing and reviewing is also a process of self-examination, and it is also a process of absorbing knowledge and completely replacing the knowledge of books with your own knowledge.

It is also a cliché to learn from the past.

Many junior high school students find chemistry difficult, but in fact, if they master these 3 points, they can get high scores. These are the most basic, but also very important parts, we must not be psychologically afraid of chemistry at the beginning, I believe that as long as you persist and master the learning methods, your junior high school chemistry scores will definitely improve.

Sorting out the wrong problem set, this habit is I developed after studying in 211, in fact, junior high school chemistry is not so complicated, it is a relatively basic entry. As long as you grasp the principles well, it will be easy to learn. In the process of learning, we should also pay attention to collecting and summarizing mistakes, and classify the problems that are easy to make mistakes and mistakes.

Then, for these wrong questions, practice several times, analyze the reasons for the mistakes, and clarify the ideas for solving the problems. This is actually one of the very good ways to check and fill in the gaps, we must pay more attention to practice, as long as we practice more, in order to avoid us from making more mistakes, so that our chemistry learning is better and better.

Ways to quickly improve junior high school chemistry:

If you grasp the textbook, you will grasp the basic knowledge, and you should focus on reading and memorizing the main principles, laws, and important conclusions and laws in the textbook. At the same time, we should also pay attention to the methods of learning research problems in chemistry, and mastering the scientific method of learning is more important than mastering knowledge. Because it improves the thinking ability of learning.

The procedure of reading a chemistry book is generally a three-step process. Take a comprehensive look at a textbook, grasp the overall content of a book, form a preliminary overall impression in your mind, and be able to outline and describe the key, difficult, key and essential issues in the textbook.

Grasp the Key On the basis of a comprehensive view, we should grasp the key points, difficulties, and key terms in the textbooks, and conscientiously ponder them repeatedly. When reading books, we should think positively, master key knowledge, and gradually break through difficult knowledge.

In short, the procedure of reading a book can be summarized as: "the whole jujube part of the jujube whole", that is, the whole perception, the part of the exploration, the whole understanding.

The object of chemical research is matter, and the composition and structure of matter determine the properties of matter, and the nature of matter restricts the way of existence, preparation method and use of matter. Therefore, when learning the properties of elemental compounds, one should grasp their structure to understand the properties of matter.

Chemistry is an experiment-based natural science. In the study of the relevant chemical properties of elemental compounds, the separation and purification of substances, identification and identification and other qualitative and quantitative analysis, it is generally necessary to verify or complete the experiment as a means to draw conclusions, so to learn chemistry well, we must pay attention to experiments.

From the use of simple common instruments, the training of basic operations to the design of complex experiments, it is necessary to operate carefully and boldly experiment. When designing experiments, it is necessary to be scientific and reasonable, that is, the device is simple, the operation is convenient, the procedure is reasonable, and the phenomenon is obvious.

The teacher's demonstration experiments in the classroom should be carefully observed and actively considered, and the principles, steps, phenomena and essentials of the experiment should be mastered.

Tips to improve your grades:

1. Pay attention to the basic knowledge of chemistry.

If you want to learn chemistry well, you must be proficient in the basic knowledge, and mastering them can lay a good foundation for learning the knowledge of elemental compounds and acids and alkalis in the future. The foundation of chemistry is very important, especially junior high school chemistry, many of which are new to students, to learn the basic knowledge of chemistry accurately, learn well, don't think that the foundation is simple and boring, this is a wrong understanding.

2. Be good at listening to lectures and taking notes.

There is a lot of chemistry content in junior high school, and the knowledge is relatively scattered, so teachers focus on the key content when lecturing. Therefore, everyone should listen carefully to the lecture and take notes carefully, which is not only conducive to reviewing after class and mastering the key points, but also can effectively prevent "distraction" during class.

However, when taking notes, on the basis of listening to what the teacher says, you should remember the key points, difficult points, doubts, and things that are not in the textbook.

3. Learning methods of chemistry experiments.

1) Experiments are a means of learning chemistry. Experiment is a scientific method for studying chemistry, and it is also an important means to learn chemistry.

2) Observation and experimentation should be combined with thinking. The observation of chemical experiments is generally carried out in the order of "before the reaction, during the reaction, and after the reaction", and at the same time, it is necessary to actively think and analyze the essential problems through the phenomenon.

3) Remember the necessary steps in the operation of chemical experiments, and do not be sloppy.

4) Experimental questions are compulsory in the chemistry exam, so in the usual learning and review process, the experimental knowledge learned should first be summarized and summarized to form a network. The high school entrance examination generally examines the basic concepts, to understand and classify, and to grasp the properties and important relationships of several important substances, such as oxygen, hydrogen, carbon and its compounds, acids, alkalis, and salts.

Secondly, it is necessary to classify and summarize some of the chemical experiments learned, such as the classification, use and basic operation of chemical instruments, and also master the calculation of basic chemical formulas and chemical equations.

The first point is to learn to grasp three things, that is, to grasp the foundation, grasp the ideas, and grasp the law. The second point is to learn to memorize more often, and the third point is to prepare two notebooks before learning chemistry. Fourth, the basic operation of chemical experiments.

1. We should pay attention to the learning of basic knowledge, which is the guarantee of improving ability. Learn chemical terms such as element symbols, chemical formulas, chemical equations and basic concepts, as well as the properties of elements and compounds. In doing questions, you should be good at summarizing and classifying question types and solving ideas.

There are internal laws between chemical knowledge, and if you master the laws, you can control the knowledge and memorize the knowledge. For example, the general law of valency, metal elements usually show positive valence, non-metallic elements usually show negative valence, the valence of elemental elements is zero, and many elements have valence, and the valence is different under different conditions.

2. After class, you should review in time and do your homework carefully, which is an important part of learning chemistry well. After-class review, post-week review, unit review, chapter review, comprehensive review, etc. Methods of revision include retelling, dictation, and making connections.

Knowledge can only be firmly grasped through multiple revisions.

3. A "mistake book" is dedicated to remembering your mistakes in exercises, homework, and exams, analyzing the reasons for mistakes, and writing down correct and good solutions. Another "good question book" for some good questions, good problem-solving methods, problem-solving skills, and problem-solving rules are written down, and reading them before the exam can achieve twice the result with half the effort.

4. Solid spoon or paper trough should be erected with one oblique two to three; The block is still good with tweezers, one horizontal, two and three slow vertical. The liquid should be bottled in a slim-mouth bottle and tagged by hand before being poured. The reading should be level with the section, low and high in the top view.

The dropper is added to the rubber head, and the vertical suspension is not stained, and it is not flat and does not fall down, and it is not forgotten to clean after use. The pallet balance must be flat, and the screw is centered; Put the object on the left to put the code on the right, and the tweezers clamp the big and then the seepage tan clamp is small; The test strip is cut small first, and the glass rod is the best for liquid testing. The test strip is moistened first, and then stuck to the rod and leans towards the gas.

The wine lamp is heated with an external flame, and two-thirds is the boundary. Stir the sulfuric acid into the water without stopping, and slowly inject it to prevent boiling splashing. The experiment first checked the air tightness, and heated the cup and bottle through the net.

After the drainage and gas collection is completed, remove the catheter first and then move the lamp.