General Review Outline for Junior Chemistry
Unit 1 Entering the World of Chemistry
I. Explore the amount of carbon dioxide in the air and the problems related to carbon dioxide.
(1) How to test for carbon dioxide? (2) How can you prove that the carbon dioxide content of inhaled air is lower than that of exhaled gas?
(3) How do you prove that a candle contains carbon and hydrogen in its composition?
II. Access to medicines
(1) How do you access dense solid medicines? How to take a powdered solid drug? There is no indication of the dosage of the general take how much?
(2) What should be noted when pouring liquid into a test tube from a fine-necked bottle?
(3) How should a measuring cylinder be read correctly? If a top-down or top-down reading is used how does the measured value relate to the true value? How to accurately measure a certain volume of liquid? (4) How to weigh a powdered drug or a solid that is easily deliquescent? How do you weigh an unknown mass of a solid or a constant mass of a solid with a balance? In what order should weights and vernier be used? If the positions of the drug and the weights are reversed and the vernier is used, can the actual mass of the drug be known?
III. HEATING OF SUBSTANCES
(1) How do you properly light or extinguish an alcohol lamp? How should spilled alcohol burn on the table? Which part of its flame has the highest temperature? How can this be proved? (2) When heating a liquid or a solid in a test tube, what should you pay attention to, respectively? What is the difference between the two?
(3) What are the possible reasons why a test tube is found to blow up when heating a medicine?
IV. Handling of Drugs and Instruments
(1) What is the sign that a glass instrument is washed clean? How to place? (2) Can the drugs be put back into the original bottle after the experiment?
Unit II The Air Around Us
I. The Main Components and Role of Air
What are the main gases contained in air? What are the uses of each gas?
II. Experiments to Investigate the Volume Fraction of Oxygen in Air
(1) What substances are usually put in a burning spoon? What are the requirements for the amount of substance given? What is the purpose?
(2) Can charcoal and sulfur be used instead of red phosphorus? Why? Can aluminum foil and wire be used instead of red phosphorus? Why? If charcoal is used in the experiment, how can the experiment be improved?
(3) What experimental phenomena were produced? What conclusions were drawn? What is the principle of the experiment?
(4) If the volume fraction of oxygen measured is significantly smaller, what are the possible causes?
III. Sources and Hazards of Atmospheric Pollutants
What are the main pollutants in the air? What are the causes? What are the hazards caused when the air is polluted?
IV. Can distinguish between pure substances and mixtures in terms of composition
What is the difference between pure substances and mixtures? Give some examples of common mixtures?
V. The basic characteristics of chemical change
What is the difference between a physical change and a chemical change? How to determine "sulfur burning in oxygen" is a chemical change?
VI, chemical reaction oxides
What is meant by chemical reaction? What are the characteristics of a chemical reaction? How many examples of chemical reactions? What is meant by oxides? Learn to identify oxides
VII. Investigating Problems Related to the Combustion of S and Al
(1) What is the difference between the combustion of S in air and in oxygen? What does it indicate?
(2) At what time is a match inserted into a gas cylinder when Al burns and why? Why is it necessary to put some fine yarn at the bottom of the cylinder?
VIII. Decomposition Reactions
What is meant by decomposition reactions? What are the characteristics of decomposition reactions? Give some examples of decomposition reactions?
Know the important role of a catalyst What role can a catalyst play in a chemical reaction? What experiments would be needed to prove that MnO2 is a catalyst for a particular reaction?
IX. Investigating the Laboratory Preparation of Oxygen
(1) There are three ways to make oxygen, what are the raw materials? What are the reaction principles? What are the advantages and disadvantages of the three methods?
(2) What instruments are needed for the device to make oxygen from KMnO4? How do you check the gas tightness of the device?
(3) What is the purpose of the milfoil when making oxygen from KMnO4? Why is the mouth of the test tube tilted slightly downward? When do you start collecting it? Why? How does it work when it ends? Why?
X. Investigating the Combustion of Carbon and Iron
(1) What are the phenomena in air and in pure oxygen?
(2) Why is it necessary to insert charcoal slowly into a gas-collecting cylinder after it has been ignited.
(3) Why is the wire coiled into a spiral? If the phenomenon of "shooting sparks" is not found, what are the reasons? How can they be improved?
(4) What chemical property of oxygen was derived from the above experiment?
XI. Symbolic expressions for reactions in this unit
(1) What are the symbolic expressions for the reactions of carbon, sulfur, phosphorus, aluminum, and iron with oxygen?
(2) three symbolic expressions for reactions to produce oxygen in the laboratory?
Unit III Water in Nature
I. Composition of Water
Based on what phenomenon can be deduced that water is a compound composed of two elements, hydrogen and oxygen?
II. Monomers and Compounds
What are the similarities between monomers and compounds? What are the differences? To learn the difference? Give a few examples of each and write the chemical formula?
Three, recognize the particulate nature of matter
What are the particles that make up matter? What relationships exist between them?
IV. Investigating the Properties of Molecules
What are the characteristics of molecules? List a few examples to prove that molecules are in constant motion? List a few examples to prove that molecules are spaced apart?
V. Purification of Water
(1) What is the difference between pure water and natural water? What is the difference between hard and soft water?
(2) What are the operations for purifying water? What is the operation with the highest degree of purification?
(3) What are the principles of water purification by alum and activated carbon?
(4) What kind of mixtures can be separated by filtration? What is the meaning of the operation of filtration "one stick, two low, three lean"?
Six, water pollution
What is the main source of water pollution? How should it be prevented?
VII. Water Conservation
Recognize the symbols of conservation, and list the common practices of water conservation in life?
Unit IV The Mystery of the Composition of Matter
I. The Composition of Atoms
(1) Know that an atom is composed of a nucleus and extra-nuclear electrons?
(2) What kinds of particles make up an atom? How do they make up an atom? Why is the whole atom not electrically active? What are the characteristics of the spatial and mass distribution of an atom?
II. Memorize the names and symbols of some common elements
III. Know the simple classification of elements
What are the three categories into which elements can be classified? What is the basis of classification? What are the characteristics of the outermost number of electrons and chemical properties of each of the elements in different categories?
Fourth, according to the atomic number in the periodic table to find the designated elements, such as: 8, 18, 28, 38, 48, etc.
Fifth, the formation of the concept of "chemical processes elements remain unchanged"
Chemical reactions before and after the change in the type of the elements and the quality of the elements? What are the microscopic causes?
VI. Extra-nuclear electrons
The role of extra-nuclear electrons in chemical reactions, why is it said that the number of outermost electrons determines the chemical properties of elements?
VII. Atoms and Ions
Know that atoms and ions of the same element can be transformed into each other. For example, how do Na and Na+, S and S2- transform into each other? In the conversion process, the number of protons, neutrons, the number of outermost electrons change? Knowing that ions are particles that make up matter, what particles are NaCl made of?
VIII. Name the valence of several common elements and atomic groups
K, Na, Ca, Zn, Mg, Cl, Al, SO4, OH, NO3, NH4, CO3 and so on.
IX. Be able to express the composition of common substances by chemical formulas
(1) Write chemical formulas based on common names; (2) Write chemical formulas based on uses; (3) Write chemical formulas based on valency.
X, can use the relative atomic mass, relative molecular mass for simple calculations of the composition of substances
(1) calculating the relative molecular mass; (2) calculating the mass ratio between the elements; (3) calculating the mass fraction of an element;
(4) based on the calculations to determine whether or not the composition of the organic matter, in addition to the elements of C, H, contains the element oxygen;
When M organic matter Equal to MH + MC does not contain element O;
Greater than MH + MC contains element O; the difference is the mass of element oxygen.
XI, can understand the composition and content of substances on the label of goods
(1) to pay attention to whether the label is the mass of the substance or the mass of the element, such as: calcium salt CaCO3-Ca, iodized salt KIO3-I;
(2) to pay attention to the unit of the mass of the unit of the label and the unit of the mass or volume of the given unit is consistent.
XII, can be based on a certain nitrogen fertilizer bags or product instructions labeled nitrogen content to deduce its purity
(1) labeled nitrogen content Actual nitrogen content (impure)
according to the chemical formula to calculate the amount of nitrogen Theoretical nitrogen content (pure) then the purity = actual nitrogen / theoretical nitrogen content × 100%
(2) to determine the advertisement of its authenticity
If the labeled nitrogen content is greater than the theoretical nitrogen content, it is a false advertisement.
XIII. Problems of averages
The actual result obtained by mixing two unequal quantities of a substance must be somewhere between the two.
Unit V. Chemical Equations
I. Recognizing the Law of Conservation of Mass and Recognizing Mass Relationships in Common Reactions
(1) Why does the mass of an iron nail increase when it rusts?
(2) Why does the mass of the remaining solid decrease after potassium permanganate is heated for some time?
II. Explain the law of conservation of mass in microscopic terms
(1) Know the microscopic reason for conservation of mass?
(2) Can infer the chemical formula of an unknown substance (note the presence or absence of coefficients)
III.Investigating Mass Relationships in Chemical Reactions
When is it necessary to conduct an experiment in a closed system.
IV. Be able to write simple chemical equations correctly
(1) Look up chemical formulas --- based on valence;
(2) Look up leveling --- counting the number of atoms, especially oxygen atoms;
(3) Look up the conditions and arrows ---- based on what you have learned or on the information given in the question.
V. Be able to perform simple calculations based on chemical equations
(1) The leveling of chemical equations must be checked;
(2) The proportionality equation must be listed;
(3) Setting up the answer must be complete;
(4) Units, x --- without units, numbers --- must be included.
Unit 6 Carbon and Carbon Oxides
I. Recognizing the Diversity of Matter
(1) Monomers of Carbon: Diamond, Graphite, C60, Carbon Nanotubes; Recognize that the same element can form different monomers;
(2) Amorphous Carbon: Properties and Uses of Charcoal, Activated Charcoal, Carbon Coke, and Carbon Black;
(3) What are the distinguishing characteristics of Diamond and graphite properties have any remarkable features? What are the main reasons? What are the uses of each?
II. Preliminary study of laboratory preparation of CO2
(1) What drugs are used? Can we use CaCO3 or Na2CO3 powder for solid? Can you use dilute hydrochloric acid or dilute sulfuric acid for liquids? What is the principle? What device is used?
(2) What is the basis for selecting the generator and collector? What are the common generation devices? What are the common collection devices?
(3) How do you test gases and check for fullness and purity (flammable gases)?
Three, know the oxygen and carbon cycle in nature , how is it realized?
IV, the greenhouse effect
Know the causes and prevention of the greenhouse effect; note the difference with air pollution, acid rain pollution prevention and control.
V. Exploring the main properties of CO2 and its uses
(1) What are the physical properties of CO2? How can it be illustrated by experiment? What uses does it have as a result of this property?
(2) Investigate the reaction of CO2 with water and clarified water gray water, and learn to design an experiment to show that CO2 can neither burn nor support combustion? What uses does this property dictate for it?
VI. Know the main properties of CO and its uses
1) What are the physical properties? (2) What are the three chemical properties? (3) How can CO be tested?
VII. Be proficient in the connections between the chemical equations in this unit.
Unit VII Fuels and Their Utilization
I. Recognize the conditions of combustion, slow oxidation and explosion and measures to prevent fire, fire extinguishing and explosion prevention
(1) the conditions of combustion and combustible combustion conditions; (2) the conditions of slow oxidation (3) the conditions in which the explosion occurs;
(4) the principles and methods of fire prevention and extinguishing; (5) the measures to prevent explosions (list of examples)
Two, experimental investigation of the conditions of combustion
(1) contact with oxygen, the temperature does not reach the ignition point; (2) the temperature reaches the ignition point, not in contact with oxygen; (3) both satisfy
Three, the control variable method of proof of the necessary conditions, for example: A, B, C conditions;
with B, C, not A, does not stand
Several products and major uses of petroleum (gasoline, diesel, liquefied petroleum gas, etc.); know that petroleum is a mixture of organic matter with different boiling points; understand the national situation of energy and resource shortages in China; know that fossil fuels are an important natural resource for mankind; formation? Utilization? What are the main constituents of fossil fuels? Substance category? Understand the environmental impact of using fuels such as H2, CH4, C2H5OH, LPG, gasoline and coal? Know how to choose the fuel with less pollution to the environment; recognize the importance of new energy development.
V. Recognize the importance of complete combustion of fuels: significance? The consequences of incomplete combustion? Measures?
VI, the unit related to the reaction of chemical equations to be memorized
Unit VIII Metals and Metallic Materials
I, understand the physical properties of metals, can distinguish between common metals and non-metals (experiments to explore the physical properties of metals, what are the differences between metals and general non-metallic physical properties? Give examples of metals with electrical conductivity, thermal conductivity, ductility, hardness, melting point and other properties? List the most common metals.
II. Recognize the important role of metallic materials in production, life and social development
List the uses of metals from the point of view that properties determine uses. Understand the properties and uses of common metals; e.g., Cu, Fe, Al.
Third, recognize that the addition of other elements can improve the properties of metals
Give examples of how the addition of other elements to metals can change their properties.
IV. Know important alloys such as pig iron and steel
What is the main difference between pig iron and steel?" What is the chemistry involved in "making steel out of steel"? List common pig iron and steel products.
V. Knowing how common metals react with oxygen
Give examples of the different activities of metals from the point of view that "metals react with oxygen with different degrees of difficulty".
Sixth, can use the order of metal activity table of the replacement reaction, and can explain some of the phenomena in daily life
(1) Recall the order of metal activity table
(2) can be used in an aluminum pot for a long time to hold vinegar, why?
(3) There are some iron salts dissolved in natural water, why does a newly bought aluminum pot leave a black mark on the surface of the water after boiling?
(4) Copper sulfate solution and slaked lime are commonly used in agriculture to configure the pesticide Bordeaux solution, why is wood passages generally used instead of iron and copper to prepare? How to test whether the prepared Bordeaux solution contains copper sulfate?
Seven, experimental investigation of acid solution, salt solution and metal replacement reaction law
(1) metal and acid replacement reaction: the requirements of the metal? Requirements for acid solutions?
(2) Replacement reaction of a metal with a salt solution: requirements for the metal? Requirements for salt? Replacement and the order of replacement:
Zn Fe and CuSO4 reaction, replacement --- first strong and then weak, so Zn first and CuSO4 reaction;
Fe and Cu (NO3) 2, AgNO3 mixed solution reaction, replacement --- first weak and then strong, so Fe first and AgNO3 solution reaction
Eight, know some common metal minerals
What are the common iron and aluminum ores, write the chemical formula of their main components.
IX. Understand the conditions under which metals rust and corrode, and discuss ways to prevent rusting
(1) Iron rust is related to oxygen and water, how can you design an experiment to prove it?
Only in contact with water, not in contact with oxygen, not rust, that: rust is related to oxygen, oxygen is essential;
Only in contact with oxygen, not in contact with water, not rust, that: rust is related to water; water is essential
At the same time, in contact with water and oxygen, rust, that: the conditions of rust is: oxygen and water are both essential.
(2) the principle of preventing rust? Methods? Name a few specific practices?
X. Understand the method of reducing iron out of iron ore (experimentally reduce iron out)
(1) the principle of ironmaking; (2) equation? (3) experiments: steps, phenomena, exhaust treatment;
XI, know the pollution of waste metals on the environment, recognize the importance of recycling metals
(1) waste batteries casually thrown away on the environment what is the impact?
(2) What is the significance of recycling waste metals?
Unit IX Solutions
I. Recognize the phenomenon of dissolution, the composition and characteristics of solutions;
II. Know that water, alcohol, gasoline, etc., are common solvents (how to use a simple method of washing the oil stains on the clothes)
III. Be able to name some common emulsification phenomena
(1) give an example of the phenomenon of emulsification; (2) use detergent to remove the oil stains and use gasoline to remove the oil stains. oil stains with gasoline to remove the principle of oil stains is different?
Four, understand the importance of solutions in production and life
(1) chemical production and chemical experiments; (2) soilless culture nutrient solution; (3) medical injection
Five, know that some substances in aqueous solution in the form of ions
Sucrose solution and salt water in the solute in what form?
VI, investigate the temperature change when NaCl NH4NO3 NaOH dissolved
Why do substances dissolved in water make the temperature of the solution show different changes? What kinds of changes in temperature? Give a typical example of each?
VII. Understanding Saturated Solutions
(1) What is the difference between a saturated solution and an unsaturated solution? How to determine whether a solution is saturated?
(2) What measures can be used to turn a bottle of nearly saturated NaCl /KNO3 /Ca(OH)2 solution into a saturated solution respectively.
VIII. Understand the meaning of solubility? View solubility properties or solubility data to plot solubility curves?
(1) what is meant by solubility? What is the meaning of "20 degrees Celsius moderate, the solubility of KNO3 is 31.6g"?
(2) What are the meanings of the horizontal and vertical coordinates on the solubility curve?What is the meaning of the point of intersection when A and B intersect at a point?
(3) What are the three ways in which the effect of temperature on the solubility of a solid can be categorized? Give one example of each?
9. Know the solubility of gases and the factors affecting it
(1) What factors affect the solubility of gases? Give an example?
(2) What is the significance of the solubility of 0.031 for O2 at 20 degrees Celsius moderate?
X. Understand the phenomenon of crystallization, the formation of alum crystals, seawater salt?
(1) What are the common methods of crystallization? What types of solutions are they applied to?
(2) How can you separate the purer KNO3 crystals from a mixture of KNO3 and a small amount of NaCl?
(3) What types of mixtures are each of the two methods of separating solid mixtures, filtration and crystallization, applicable to?
XI, preliminary learning to prepare a certain mass fraction of the solution
(1) What instruments are needed? The main steps?
(2) the difference between a solid as a solute and a liquid as a solute (or concentrated solution dilution)?
XII, can carry out simple calculations of solute mass fraction
(1) solute mass fraction = solute mass / solvent mass * 100%;
(2) dilution: the mass of the solute remains unchanged
M concentration *C concentration % = M dilution *C dilution % or M concentration *C concentration % = (M concentration + M water ) *C dilution %
(3) and the equation of the Comprehensive Calculations
Mass of solution after reaction = Mass of solution before reaction (without insoluble impurities) + - Mass of gas produced - Mass of precipitate produced
Unit 10 Acids and Bases
I. Will you test the acidity and alkalinity of a solution with acid-base indicators (or experiment with the changes in the sap of flowers of certain plants in acidic and basic solutions)?
(1) What two types of acid-base indicators are commonly used? What colors do they show when exposed to acidic or alkaline solutions?
(2) What kind of flower sap is suitable as an acid-base indicator?
Second, recognize the corrosiveness of acids and bases
(1) Acids and bases have different degrees of corrosiveness;
(2) Concentrated H2SO4 and NaOH accidentally stained on the skin or clothes should be how to deal with?
Three, the initial learning to dilute common acid or base solutions: how to dilute concentrated sulfuric acid?
Four, experiments to explore the important properties and uses of acids
(1) hydrochloric acid, sulfuric acid and its main properties and uses: to explore the volatility of concentrated hydrochloric acid? When making wine to adjust the acidity, why use dilute sulfuric acid, but not hydrochloric acid? Why not use concentrated hydrochloric acid to produce carbon dioxide in the laboratory?
(2) What are the uses of hydrochloric acid?
(3) Learn to investigate the water absorption of concentrated sulfuric acid? What are the uses of concentrated sulfuric acid and can O2 , H2 , CO2 , CO , NH3 , CH4 all be used as desiccants with concentrated sulfuric acid?
(4) What are the ****same chemical properties of dilute hydrochloric acid and dilute sulfuric acid? With acid-base indicators; with active metals; with metal oxides; with bases; with certain salts; why do they have similar chemical properties?
V. Experimental investigation of the main properties and uses of bases
(1) Experimental investigation of the water absorption of NaOH solids?Uses of NaOH solids?Can O2 , H2, CO2, CO, NH3, CH4 all be used as desiccants with NaOH?
(2) What are the common names of NaOH and Ca(OH)2, and the uses of Ca(OH)2? What should be noted about the use of NaOH?
VI.Learn to investigate the chemical properties of NaOH and Ca(OH)2 through experiments?
(1) with indicators; (2) with acids; what is meant by neutralization reaction? (3) with certain non-metallic oxides; (4) with certain salts; why do they have similar chemical properties?
VII. Know the effect of acidity and alkalinity on life activities and crop growth
(1) What is the importance of knowing the acidity and alkalinity of a solution in practical production and life?
(2) What are the applications of neutralization reactions in practical production and life? For example, how to treat excessive stomach acid? How to deal with sulfuric acid in waste liquid? How to deal with mosquito bites?
VIII, will use PH test paper to test the acidity and alkalinity of solutions
(1) How to test the acidity and alkalinity of solutions or soil with PH test paper?
IX. Be proficient in the chemical equations in this unit.
Unit 11 Salt Fertilizers
I. Understand the names and common names of salts such as NaCl, NaCO3 , NaHCO3 , CaCO3 and their uses in daily life.
II. Learn the purification of crude salt, crude salt purification process of evaporation operations need what instruments? Steps? Which instruments are used? Evaporation when to stop heating why?
Three, how to test CO32-? What are the common precipitates?
Four, preliminary understanding of common complex decomposition reaction, can be used to explain some phenomena related to daily life
(1) Complex decomposition reaction can occur under what conditions?
(2) Learn to determine whether some substances can be decomposed?
V. Know the names and roles of some common fertilizers
(1) What are the elements that are in high demand for plant growth?
(2) What is the role of nitrogen fertilizer / phosphate fertilizer / potash respectively? What is meant by compound fertilizer? Give some examples?
(3) How to identify nitrogen/phosphorus/potassium fertilizers?
VI. Recognize the importance of the rational use of fertilizers and pesticides to protect the environment; irrational use will bring what kind of environmental problems? What measures should be taken?
Unit XII Chemistry and Life
I. Understand the organic matter important to life activities, such as: sugar, starch, fats and oils, amino acids, proteins, vitamins and so on.
(1) What are the physiological functions of sugars, fats, proteins and vitamins? Which foods are rich in sugars or fats or proteins or fiber?
(2) What is the role of amino acids in the body? (3) The metabolic process of starch.
II. Knowing that certain substances (CO, formaldehyde, aflatoxin) are harmful to human health, and recognizing that a knowledge of chemistry can help people defend themselves against harmful substances.
(1) CO how to make people poisoned? (2) What is the reason for formaldehyde poisoning?
(3) What causes aflatoxin to poison people?
Three, to understand the role of certain elements such as: Ca, Fe, Zn, I, F, etc. on human health
Body lack of Ca, Fe, Zn elements on the human body, respectively, what are the effects?
Four, preliminary understanding of the development of chemical science in helping people to overcome disease and nutritional health care in the significant contribution
Five, can distinguish between organic and inorganic substances from the composition. List some common organic matter in life, recognize the importance of organic matter to human life.
VI, to understand the common synthetic fibers, plastics, synthetic rubber and its application; to understand the impact of synthetic materials on people and the environment; to understand the development of new materials and the close relationship between social development.
seven, with simple experiments to distinguish between cotton thread dimensions, wool fibers and synthetic woven not material?
VIII, with simple experiments to distinguish between thermosetting and thermoplastics? Distinguish between polyethylene and polyvinyl chloride plastics with simple experiments?