Seek to sort out the chemistry knowledge of the third year of junior high school, and the more refin

I think it's very well organized, and it's very detailed, you can take a look.

1. Chemical change: the change of other substances is generated.

2. Physical change: no change in other substances.

3. Physical properties: properties that do not need to undergo chemical changes, such as: color, state, density, odor, melting point, boiling point, hardness, water solubility, etc.

4. Ions. 1) Concept: Charged atoms or clusters of atoms.

2) Representation method and significance: such as Fe3+: one iron ion with 3 units of positive charge.

5. Elements. 1) Concept: A general term for a class of atoms with the same number of nuclear charges (protons).

2) The number of protons determines the type of element.

3) The chemical properties of an element are closely related to the number of electrons in the outermost shell of an atom.

6. The law of conservation of mass.

1) Concept (reactants and products do not change in mass before and after).

2) Cause (three invariants - the type, number, and mass of atoms do not change before and after the reaction).

3) Calculations related to chemical equations.

Note: The law of conservation of mass only applies to chemical changes, not to physical changes.

The mass of a substance that does not participate in the reaction and the mass of a substance that is not a product cannot be counted in the "sum".

Consider whether a substance in the air participates in the reaction or if a substance (e.g. gas) is missing.

7. Preparation method of carbon dioxide.

1) Laboratory preparation of carbon dioxide.

Principle: Reaction with limestone and dilute hydrochloric acid:

CaCO3+2HCl==CaCl2+H2O+CO2 Solid-liquid non-heating device is selected.

Gas collection method: upward air exhaust method.

Verification method: The prepared gas is passed into the clarified lime water, and if it can become turbid, it is carbon dioxide.

Full inspection method: Use a lit wooden strip and put it at the mouth of the gas collection bottle, and the wooden strip is extinguished. is already full of carbon dioxide.

2) Industrial production method of carbon dioxide:

Calcined limestone: caCO3 high temperature cao + CO2 quicklime and water reaction can obtain hydrated lime: cao + h2o = ca(oh)28, solubility table memory formula.

Potassium sodium ammonium salts are all soluble, and nitrates are the same.

Alkali dissolves ammonium, potassium, sodium, barium calcium, sulfates, and barium calcium.

Chloride except silver mercurous, carbon phosphate is mostly insoluble.

The color of the solid.

1. Red solid: copper, iron oxide.

2. Green solid: basic copper carbonate.

3. Blue solid: copper hydroxide, copper sulfate crystals.

4. Purple-black solid: potassium permanganate.

5. Light yellow solid: sulfur.

6. Colorless solids: ice, dry ice, diamond.

7. Silvery-white solid: silver, iron with coarse, magnesium, aluminum, mercury and other metals.

8. Black solid: iron powder, charcoal, copper oxide, manganese dioxide, ferric tetroxide, (carbon black, activated carbon).

9. Reddish-brown solid: iron hydroxide.

10. White solid: sodium chloride, sodium carbonate, sodium hydroxide, calcium hydroxide, calcium carbonate, calcium oxide, copper sulfate, phosphorus pentoxide, magnesium oxide.

The color of the liquid.

11. Colorless liquid: water, hydrogen peroxide.

12. Blue solution: copper sulfate solution, copper chloride solution, copper nitrate solution.

13. Light green solution: ferrous sulfate solution, ferrous chloride solution, ferrous nitrate solution.

14. Yellow solution: ferric sulfate solution, ferric chloride solution, nitric acid iron solution.

15. Fuchsia solution: potassium permanganate solution.

16. Purple solution: litmus solution.

An important ingredient in common mixtures in junior high school chemistry.

1. Air: nitrogen (N2) and oxygen (O2).

2. Water gas: carbon monoxide (CO) and hydrogen (H2).

3. Gas: carbon monoxide (CO).

4. Natural gas: methane (CH4).

5. Limestone marble: (caCO3).

6. Pig iron steel: (Fe).

7. Charcoal, coke, carbon black, activated carbon: (c).

8. Rust: (Fe2O3).

Common name for common substances in junior high school chemistry.

1. Sodium chloride (NaCl): table salt.

2. Sodium carbonate (Na2CO3): soda ash, soda, mouth alkali.

3. Sodium hydroxide (NaOH): caustic soda, caustic soda, caustic soda.

4. Calcium oxide (CAO): quicklime.

5. Calcium hydroxide (Ca(OH)2): hydrated lime, slaked lime.

6. Carbon dioxide solid (CO2): dry ice.

7. Hydrochloric acid (HCl): hydrochloric acid.

8. Basic copper carbonate (Cu2(OH)2CO3): patina.

9. Copper sulfate crystals (CuSO45h2o): blue alum, bile alum.

10. Methane (CH4): biogas.

11. Ethanol (C2H5OH): alcohol.

12. Acetic acid (CH3COOH): acetic acid.

13. Hydrogen peroxide (H2O2): hydrogen peroxide.

14. Mercury (Hg): mercury.

15. Sodium bicarbonate (NaHCO3): baking soda.

Read and comprehend textbooks carefully and carefully.

Chemistry textbooks are textbooks that systematically explain the basic content according to the syllabus. When you grasp the textbook, you also grasp the basics. We should focus on reading and memorizing the principles, laws, and important conclusions and laws in the textbook. Reading chemistry textbooks is generally a three-step process.

Comprehensive view: To read a textbook comprehensively, it is necessary to be able to understand the key, difficult, key and essential issues in the textbook in an outline.

Grasp the key: grasp the key points, difficulties and key terms in the textbook, and carefully ponder them repeatedly.

Rational thinking: to think positively, sort out clues, and often summarize and summarize.

Chemistry memorization is about methods.

Chemistry should not memorize new knowledge in isolation, but should organically link and memorize new and old knowledge. For example, when learning redox reactions, it is necessary to memorize them in connection with the knowledge of valency learned earlier, which not only consolidates the old knowledge, but also deepens the understanding of the new knowledge.

It is useless to memorize chemistry knowledge points in isolation, the inertia of chemistry is very large, and the same is true of junior high school chemistry, and the combination of new knowledge and the correlation that has been learned before, so that you can learn to look at problems systematically.

Suggestions on learning methods for top students.

1, The periodic table is very important, but junior high school usually only memorizes the first 18 elements, remember, you must memorize him, this is the basis of your problem solving.

2. The physical properties of matter, chemical properties should be familiar and easy to mix, such as "blue flame" and "light blue flame" clearly (chemistry every time you learn a substance, you should remember a substance, don't be lazy, when learning the next substance, you should compare and remember the substance you learned last time, otherwise, if you learn too much material, you will be very confused and collapse when you do the problem).

3. It's hard to remember clearly, this, the teacher wants to teach the formula.

4. In junior high school, you have to learn simple calculations, this one needs to be practiced more, and it is simple to practice more super pants, all of which are modes, but generally this kind of problem requires you to deduce it first, then write equations, and then calculate.

5. The equation should be memorized, memorized clearly, and memorized proficiently.

6. Valency, the teacher should also teach the formula, the importance of it in junior high school is to write chemical formulas, and in high school, you should be advanced, and ask you to write equations or trims by yourself. Mills.