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Little knowledge of chemistry
1. Ask for chemical tips 100 chemical tips.

First, the chemical maximum is 1. The most abundant metal element in the earth's crust is aluminum. 2. The most abundant nonmetallic element in the earth's crust is oxygen. The most abundant substance in the air is nitrogen. The hardest substance in nature is diamond. 5. The simplest organic matter is methane. 6. The most active metal in the metal activity sequence table is potassium. 7. The oxide with the lowest relative molecular weight is water. 8. Under the same conditions. The most conductive metal is silver. 10. The atom with the smallest relative atomic mass is hydrogen. 1 1. The metal with the lowest melting point is mercury. 12. The most abundant element in human body is oxygen. 13. The element with the most kinds of compounds is carbon. 14. The three kinds of particles that make up matter are molecules, atoms and ions. 2. Hydrogen, carbon monoxide and carbon. 3 and hydrogen, which are often used to reduce copper oxide, have three advantages as fuel: rich resources, high calorific value, and the product after combustion is water, which does not pollute the environment. There are generally three kinds of particles that make up atoms: protons, neutrons and electrons. There are only three kinds of ferrous metals: iron, manganese and chromium. Elements that make up a substance can be divided into three categories, namely (1) metallic elements, (2) nonmetallic elements and (3) rare gas elements. 7. There are three kinds of iron oxides, the chemical formula is (1)FeO, (2)Fe2O3, (3) Fe3O4.8, and the characteristic of the solution is three (65434). (2) stability; (3) mixture. 9. The chemical equation has three meanings: (1) indicates what substances participate in the reaction and what substances are generated as a result; (2) The particle number ratio of molecules or atoms between reactants and products; (3) Represents the mass ratio of reactants to products. Chemical equations have two principles: based on objective facts; According to the law of conservation of mass, pig iron can be generally divided into three types: white iron, gray iron, ductile iron, carbon steel, high carbon steel, medium carbon steel, low carbon steel, and iron ore commonly used in ironmaking. (2) Magnetite (Fe3O4); (3) siderite (FeCO3). 13. There are mainly three kinds of steelmaking equipment: converter, electric furnace and open hearth furnace. 14. The three reaction conditions that are often related to temperature are ignition, heating and high temperature. 15. There are two ways to change saturated solution into unsaturated solution: (65438+. There are three ways to change unsaturated solution into saturated solution: cooling, adding solute and evaporating solvent at constant temperature. (Note: For substances whose solubility decreases with temperature, such as calcium hydroxide solution changing from saturated solution to unsaturated solution: cool and add solvent; There are three ways to change unsaturated solution into saturated solution: raising temperature, adding solute and evaporating solvent at constant temperature) 16. There are generally three ways to collect gas: drainage, upward evacuation and downward evacuation. 17. There are three main reasons for water pollution: (1) waste residue, waste gas and waste water in industrial production; (2) Discharging domestic sewage at will; (3) Pesticides and fertilizers used in agricultural production flow into rivers with rainwater 18 There are three kinds of fire extinguishers commonly used: foam extinguisher; Dry powder fire extinguisher; Liquid carbon dioxide fire extinguisher. 19. The solubility of solid substances can be divided into three categories with the change of temperature: (1) The solubility of most solid substances increases with the increase of temperature; (2) The solubility of a few substances is little affected by temperature; (3) The solubility of a few substances decreases with the increase of temperature. 20. There are three reasons why CO2 can put out a fire: it can't burn, it can't help combustion, and its density is higher than that of air. 2 1. Simple substances can be divided into three categories: metallic simple substances; Non-metallic simple substance; Rare gas elements. 22. The three most important fossil fuels in the world today are coal, oil and natural gas. 23. The three black oxides that should be remembered are copper oxide, manganese dioxide and ferroferric oxide. 24. Hydrogen and carbon have three similar chemical properties: stability at room temperature, flammability and reducibility. 25. There are three kinds of light blue in the textbook: (1) liquid oxygen is light blue; (2) When sulfur burns in the air, it has a faint light blue flame; (3) There is a light blue flame when hydrogen burns in air; (26) Three blue colors related to copper: (1) copper sulfate crystal; (2) copper hydroxide precipitation; (3) copper sulfate solution. 27. The filtration operation has "triple inclination": (1) The lower end of the funnel is close to the inner wall of the beaker; (2) the end of the glass rod gently leans against the third layer of filter paper; (3) The edge of the beaker containing the liquid to be filtered is close to the glass frame for drainage. 28. Qifupa Electric Appliance consists of three parts: a spherical funnel, a container and an air duct. 29. The flame of alcohol lamp is divided into three parts: external flame, internal flame and flame core, of which the external flame has the highest temperature. 30. Medication and medication have the principle of "three noes": (1) unnecessary. (2) Don't put your nose to the mouth of the container to smell the smell of gas; (3) Don't taste the medicine. 3 1. Write the CuSO4 and state of the following substances. 5H2O): blue solid basic copper carbonate (copper rust): green solid black solid: carbon powder, copper oxide, manganese dioxide and ferroferric oxide white solid: anhydrous copper sulfate (CuSO4), potassium chlorate, potassium chloride, magnesium oxide, sodium chloride, calcium carbonate, sodium carbonate and zinc sulfate purple black: potassium permanganate light green solution: ferrous sulfate (FeSO4)32. Conditions for burning combustible materials. Make the temperature of combustible materials reach the ignition point. 33. Gases containing diatomic molecules: H2, oxygen, N2, chlorine, F234. Which part of the atomic structure determines the following points: ①. The types of elements are determined by the number of protons; ② The classification of elements is determined by the number of outermost electrons; ③ The chemical properties of elements are determined by the number of outermost electrons; ④ The valence of elements is determined by the number of outermost electrons; ⑤ Organic compounds studied: CH4 (methane), C2H5OH (alcohol, ethanol), CH3OH (methanol), CH3COOH (acetic acid, acetic acid) 36. Macroscopically and microscopically, the law of conservation of mass can be summarized as five invariants, two definite changes, and one possible change: (1) Five invariants: macroscopically understanding the types of elements. (2) Two certain changes: recognizing that the types of substances must change from a macro perspective, and the types of molecules must change from a micro perspective; (3) A possible change: the sum of molecules may change. 37. Two simple substances of carbon: graphite and diamond (formation reason: different arrangement of carbon atoms). 38. Write down the following.

2. Little knowledge of chemistry

Common sense (1) Why can fruit relieve alcoholism?

Excessive drinking is often a sign of drunkenness. Drunkenness is often accompanied by symptoms such as increased language, ineffective tongue, fever and numbness in cheeks, dizziness, and unstable standing ... These are all manifestations of drunkenness, and it is necessary to sober up.

Many people know that eating fruit or drinking 1-2 clean vinegar can relieve hangover. What is the truth?

This is because fruits contain organic acids, for example, apples contain malic acid, oranges contain citric acid, and grapes contain tartaric acid. The main component of wine is ethanol, and organic acids can interact with ethanol to form esters to achieve the purpose of hangover. Similarly, vinegar can relieve alcoholism because it contains 3-5% acetic acid, which can react with ethanol to produce ethyl acetate.

Although the fruit with sour taste and vinegar can alleviate the anesthetic effect of excessive ethanol, the effect is not ideal due to the interference of many factors in the above esterification reaction. Therefore, the best way to prevent drunkenness is not to drink too much.

Common sense (2) Fried dough sticks and chemistry

Fried dough sticks are one of the traditional popular foods in China. They are not only cheap, but also crispy and delicious, suitable for all ages.

Fried dough sticks have a very long history. In ancient China, fried dough sticks were called "coolers". Liu Yuxi, a poet in the Tang Dynasty, described the shape and making process of fried dough sticks in a poem about cold weapons: "When you rub jade with your hands, you will find that it is blue, oily and light yellow; It doesn't matter if you sleep in the spring at night, but the beauty of the plaque is wrapped around your arm. " How vividly this poem depicts fried dough sticks! But when you eat crispy and delicious fried dough sticks, have you thought about the chemical knowledge in the process of making fried dough sticks?

Let's take a look at the making process of fried dough sticks: first, mix the dough, that is, add fresh yeast or old noodles (fermented noodles) and flour to knead the dough to a certain extent, then add proper amount of soda ash, salt and alum to knead the dough, and then cut it into strips with a thickness of 1cm and a length of 10cm. Every two strips are stacked up and down, pressed with narrow wooden strips in the middle, and stretched after rotation.

During the fermentation process, due to the propagation and secretion of enzymes (mainly glucoamylase and alcoholase) in dough, a small part of starch is converted into glucose, and then from glucose to ethanol, producing carbon dioxide gas. At the same time, some organic acids are produced, which react with ethanol to produce aromatic esters.

The carbon dioxide gas produced by the reaction makes the dough produce many small holes and expand. The presence of organic acids will make dough sour. The purpose of adding soda ash is to neutralize excess organic acid, produce carbon dioxide gas and further expand the dough. At the same time, soda ash is dissolved in water and hydrolyzed; After frying in a hot oil pan; Due to the production of carbon dioxide, fried fritters are more loose.

From the above reaction, we may be worried. Isn't there sodium hydroxide in the fritters? How can fried dough sticks with such strong alkalinity taste delicious? However, its ingenuity is also here. When free sodium hydroxide appears in the dough, alum in the raw material immediately reacts with it, so that the free sodium hydroxide becomes aluminum hydroxide. Gel solution or dry gel of aluminum hydroxide is used as antacid in medicine, which can neutralize gastric acid and protect ulcer surface, and can be used to treat hyperacidity, gastric ulcer and duodenal ulcer. The main component of the common stomach medicine "Weishuping" is aluminum hydroxide. Therefore, some Chinese medicine prescriptions say that fried dough sticks have inhibitory effect on gastric acid and have certain curative effect on some stomach diseases.

3. Life tips about chemistry ~ Help me answer 20 life tips about chemistry.

Don't cook spinach and tofu together. The vitamin content of spinach is among the best among all kinds of vegetables. One catty of spinach contains about 133 grams of carotene (raw material for making vitamin A); Contains vitamin c138g, which is more than twice as high as that of the well-known tomato.

Therefore, eating spinach often is good for health, and also has a good effect on anemia, hypertension, rickets and tooth bleeding. Spinach contains a lot of oxalic acid and is not suitable for cooking with tofu.

Because magnesium chloride (bittern MgCI2) or gypsum (CaSO4) in tofu reacts with oxalic acid, it generates water-insoluble magnesium oxalate or calcium oxalate, which is deposited on the blood vessel wall, affecting blood circulation and having a great impact on the normal development of children. Oxalic acid in spinach can also affect children's absorption of calcium.

However, this shortcoming of spinach can be remedied, as long as the spinach is dug out with hot water first, and then soaked in cold water for about 20 minutes, so that most oxalic acid can be leached out. 2。

Is the boiler water drinkable? The water used for steaming steamed bread or side dishes at home is called boiler water. This kind of boiler water can't be drunk, nor can it be used for cooking rice or porridge. What is the reason? As we all know, water contains trace amounts of nitrate. When water is heated for a long time, the concentration of nitrate increases relatively due to the continuous evaporation of water, and it is decomposed into nitrite by heating.

Nitrite does great harm to human health. It can denature hemoglobin in human blood, so that it can no longer combine with oxygen, leading to early hypoxia.

Nitrite can also reduce human blood pressure, which can lead to collapse in severe cases. Modern medicine has proved that nitrite is also a strong carcinogen.

Therefore, boiler water cannot be drunk. 3。

When people buy mutton, they often judge the freshness of the meat according to its color. What is the reason? Because of incomplete bleeding, hemoglobin remains and iron in hemoglobin exists in the form of divalent ions when slaughtering pigs and sheep, fresh meat is bright red. With the development of meat, ferrous ions are gradually oxidized into trivalent iron ions by air, which makes the meat appear dark red.

4。 10 Preserved eggs should not be eaten in various foods: a certain amount of lead is needed to make preserved eggs, and eating more will cause lead poisoning and calcium deficiency.

Stinky Tofu: Stinky Tofu is easily contaminated by microorganisms during fermentation, and contains a lot of volatile basic nitrogen and hydrogen sulfide, which is decomposed by protein. Eating more is harmful to human body. MSG: The intake of MSG per person per day should not exceed 6 mg. Excessive intake will increase the content of glutamic acid in blood, limit the utilization of necessary calcium and magnesium divalent cations, cause short-term headaches, nausea and other symptoms, and have adverse effects on human reproductive system.

Instant noodles: Instant noodles contain edible pigments and preservatives harmful to human body. Eating them often is harmful to health. Sunflower seeds: Sunflower seeds contain unsaturated fatty acids. Eating too much will consume a lot of alkali in the body and affect the function of liver cells.

Spinach: Spinach is nutritious, but it contains oxalic acid. Zinc and calcium in food will combine with oxalic acid and be excreted, thus causing zinc and calcium deficiency in human body. Pig liver: 1000 g pig liver contains more than 400 mg of cholesterol. A person who ingests too much cholesterol will lead to arteriosclerosis and aggravate cardiovascular diseases.

Roasted beef and mutton: In the process of barbecue, beef and mutton will produce harmful substances such as benzopyrene, which is a substance that induces cancer. Pickled vegetables: Pickled vegetables will contain carcinogen ammonium nitrite if they are not pickled well.

Fried dough sticks: Alum in fried dough sticks is an inorganic substance containing aluminum. If you eat fried dough sticks every day, aluminum is difficult to be excreted by the kidneys, which is toxic to the brain and nerve cells, and even leads to Alzheimer's disease. Eating detoxified food regularly is good for healthy pig blood: Chinese medicine believes that pig blood is good for relaxing bowels and removing intestinal dirt.

Modern medicine has confirmed that the plasma protein in pig blood can be decomposed by gastric acid in human body, producing a decomposition product of detoxifying and clearing intestines, which can react with dust and harmful metal particles invading human body and then be discharged into digestive tract. Kelp: Chinese medicine believes that kelp is cold and salty, and has the functions of softening and resolving hard mass, clearing away heat and promoting diuresis, reducing fat and lowering blood pressure.

Kelp can also prevent leukemia (hematologic cancer). Carrots: Carrots are also effective antidotes.

It is not only rich in carotene, which can increase human vitamin A after eating, but also contains a lot of pectin. The combination of this substance and mercury can effectively reduce the concentration of mercury in blood and accelerate the elimination of mercury ions in the body, so it has the function of mercury discharge. 5。

The color, smell and taste of food are mostly artificially colored, and food pigments are added during production. Some foods are colored because they contain some natural pigments.

For example, the green leaves of vegetables and immature fruits are chlorophyll, the red of tomatoes is tomato pigment, and the shells of shrimps and crabs contain stilbene, which can turn red when heated. The aroma of food comes from volatile substances such as alcohols, aldehydes, ketones and esters.

Fish, meat and eggs are rich in protein. Protein itself has no umami flavor, but it is hydrolyzed into various amino acids after cooking, and it tastes delicious. Glutamate is the most delicious amino acid.

"MSG" is the sodium salt of glutamic acid. Sugar will not feel sweet when diluted to 200 times with water, while monosodium glutamate will taste when diluted to 3000 times with water! Recently, a powerful monosodium glutamate was developed, which was made of sodium glutamate and inosine, and its flavor was 40 times that of monosodium glutamate.

Shrimp, crab, snail and clam contain a lot of succinic acid, so they have a unique flavor that people like. The aroma of cinnamon comes from cinnamaldehyde, while the aroma of distiller's yeast comes from fusel alcohols and esters produced during fermentation.

The aroma of banana is volatile isoamyl acetate, and the aroma of citrus comes from nerol. As for the fragrance of cakes and sweets, it is due to the addition of artificial fruit essence.

In China, people are used to dividing taste into five flavors: sour, sweet, bitter, spicy and salty. Sour taste is caused by hydrogen ions ionized from various organic acids, and the strength of sour taste depends on the concentration of hydrogen ions.

Vinegar contains about 3%-5% acetic acid, sauerkraut contains lactic acid, sour taste in fruits, drinks or sweets comes from citric acid, tartaric acid, malic acid and vitamin C, and sweet taste is caused by sugars such as sucrose, fructose, glucose, maltose and lactose.

When making cakes, biscuits, popsicles and ice cream, a proper amount of saccharin is often added.

4. Little knowledge of chemistry

Common sense (1) Why can fruit relieve hangover? Excessive drinking is often a sign of drunkenness. There are more signs of drunkenness, more language, tongue failure, fever and cheek numbness, dizziness and instability ... all these are signs of drunkenness. At this time, I will have a hangover.

Many people know that eating fruit or drinking 1-2 clean vinegar can relieve hangover. What is the truth? This is because fruits contain organic acids, for example, apples contain malic acid, oranges contain citric acid, and grapes contain tartaric acid. The main component of wine is ethanol, and organic acids can interact with ethanol to form esters to achieve the purpose of hangover.

Similarly, vinegar can relieve alcoholism because it contains 3-5% acetic acid, which can react with ethanol to produce ethyl acetate. Although the fruit with sour taste and vinegar can alleviate the anesthetic effect of excessive ethanol, the effect is not ideal due to the interference of many factors in the above esterification reaction.

Therefore, the best way to prevent drunkenness is not to drink too much. Common sense (2) Fried dough sticks and chemical fried dough sticks are one of the traditional popular foods in China. They are not only cheap, but also crispy and delicious, suitable for all ages.

Fried dough sticks have a very long history. In ancient China, fried dough sticks were called "coolers".

Liu Yuxi, a poet in the Tang Dynasty, described the shape and making process of fried dough sticks in a poem about cold weapons: "When you rub jade with your hands, you will find that it is blue, oily and light yellow; It doesn't matter if you sleep in the spring at night, but the beauty of the plaque is wrapped around your arm. " How vividly this poem depicts fried dough sticks! But when you eat crispy and delicious fried dough sticks, have you thought about the chemical knowledge in the process of making fried dough sticks? Let's take a look at the making process of fried dough sticks: first, mix the dough, that is, add fresh yeast or old noodles (fermented noodles) and flour to knead the dough to a certain extent, then add proper amount of soda ash, salt and alum to knead the dough, and then cut it into strips with a thickness of 1cm and a length of 10cm. Every two strips are stacked up and down, pressed with narrow wooden strips in the middle, and stretched after rotation.

During the fermentation process, due to the propagation and secretion of enzymes (mainly glucoamylase and alcoholase) in dough, a small part of starch is converted into glucose, and then from glucose to ethanol, producing carbon dioxide gas. At the same time, some organic acids are produced, which react with ethanol to produce aromatic esters. The carbon dioxide gas produced by the reaction makes the dough produce many small holes and expand.

The presence of organic acids will make dough sour. The purpose of adding soda ash is to neutralize excess organic acid, produce carbon dioxide gas and further expand the dough. At the same time, soda ash is dissolved in water and hydrolyzed; After frying in a hot oil pan; Due to the production of carbon dioxide, fried fritters are more loose. From the above reaction, we may be worried. Isn't there sodium hydroxide in the fritters? How can fried dough sticks with such strong alkalinity taste delicious? However, its ingenuity is also here.

When free sodium hydroxide appears in the dough, alum in the raw material immediately reacts with it, so that the free sodium hydroxide becomes aluminum hydroxide. Gel solution or dry gel of aluminum hydroxide is used as antacid in medicine, which can neutralize gastric acid and protect ulcer surface, and can be used to treat hyperacidity, gastric ulcer and duodenal ulcer.

The main component of the common stomach medicine "Weishuping" is aluminum hydroxide. Therefore, some Chinese medicine prescriptions say that fried dough sticks have inhibitory effect on gastric acid and have certain curative effect on some stomach diseases. Common sense (3) Discrimination of real gold With the continuous improvement of people's living standards, more and more people wear gold ornaments. When buying, people always want to buy pure gold, which is called pure gold.

Real gold is glittering and heavy, with a specific gravity of 19.3 (g/cm 3). It is not afraid of corrosion, and its color remains unchanged after thousands of years. Although real gold can shine, it is not necessarily real gold, such as fool's gold and artificial imitation gold (such as titanium nitride). )

Fool's gold refers to pyrite (FeS2) or chalcopyrite (CuFeS2) that can emit golden luster. They often fool people who lack mineral knowledge with their charming beauty and get their nicknames. Fool's gold, imitation gold and real gold are the same color, and it is difficult to distinguish between true and false.

But as soon as they touched the touchstone, their "true colors" were exposed. Looks like the touchstone is mysterious. In fact, it is just a very common stone in nature, gray-black, goose-shaped, and has weathered into the shape of a goose egg.

When testing, as long as the test object is scratched on the touchstone, its true colors will be revealed: the stripes drawn by pyrite are black, and the stripes drawn by chalcopyrite are dark green; And what about real gold? The scratches left on the touchstone turned golden again. "Gold is not enough."

Natural gold is still not absolutely pure, what's more, gold is rare and expensive. So many gold ornaments add some copper and silver to gold to make alloys. When people buy gold, they are faced with the problem of how to identify the uniform purity of gold and determine its color (gold content).

With the "golden eye" of the touchstone, we can not only distinguish the authenticity of gold; You can also see through the pros and cons of gold (in terms of "K", 24K… 100% is the best; 18K…75% is the second; 12K...50% is bad) This is because the colors of gold ornaments with different colors are slightly different. People extract standard gold bars with different gold contents in proportion in advance, draw color marks with known content one by one on the touchstone, then cut the gold ornaments to be tested on the same touchstone, compare the two, and finally judge the color by experienced experts.

This method is simple and feasible, but there are some errors. We must find a more accurate method and choose an instrument with sharper eyes. With the development of science and technology, laser gold detector was invented abroad.

The laser beam irradiates gold, alloy or imitation gold, and turns them into vapor respectively, showing different spectral lines and their intensities, so that it can be correctly identified, and the operation is simple without worrying about the loss of gold. During inspection, the laser-made knife is smaller than the needle tip, and the sample loss is less than one billionth of a gram, which is really negligible and is very popular with customers and jewelers. Lushan Mountain, an apparatus for hanging gold ornaments in the shape of * * * ",is worthy of the name. (。

5. What are the high school chemistry common sense summaries?

I. Common names Inorganic parts: soda ash, soda ash, natural alkali, oral alkali: Na2CO3 baking soda: NaHCO3 baking soda: Na2S2O3 gypsum (raw gypsum): CaSO4.2H2O gypsum: 2CaSO4 .H2O fluorite: CaF2 barite: BaSO4 (nontoxic): NH4HCO3 limestone, marble: CaCO3 quicklime: CaO salt: NaCl. Hydrated lime: Ca(OH)2 mirabilite: Na2SO4 7H2O (laxative) caustic soda, caustic soda, caustic soda: NaOH green alum: FaSO4 7H2O dry ice CaCl2 _ 2 (mixture) epsom salt: MgSO _ 4·7H2O bile alum, blue alum: CuSO _ 4·5H2O hydrogen peroxide: H2O2 alum: ZnSO _ 4. Timely: SiO2 _ 2 corundum: Al2O3 water glass, sodium silicate, mineral glue: Na2SiO3 iron red, iron ore: Fe2O3 magnetite: Fe3O4 pyrite, pyrite: FeS2 patina. Malachite: Cu2 (OH)2CO3 siderite: FeCO3 chalcopyrite: Cu2O Bordeaux solution: Ca (OH)2 and CuSO4 stone sulfur mixture: Ca (OH)2 and S glass Main components: Na2SiO3, CaSiO3, SiO2 superphosphate (main components): Ca (H2PO4). 2 and CaSO4 superphosphate (main components): Ca (H2PO4)2 natural gas, biogas and pit gas (main components): CH4 water gas: CO and H2ammonium ferrous sulfate (light blue-green): Fe (NH4)2 (SO4). 2. Photochemical smog that turns pale green when dissolved in water: aqua regia, a toxic gas produced by NO2 under illumination, is formed by mixing concentrated HNO3 and concentrated HCl in the volume ratio of 1:3. Thermite: Al+Fe2O3 or other oxides. Urea: carbon monoxide (NH2). Organic part: chloroform: CHCl3 calcium carbide: CaC2 calcium carbide gas: C2H2 (acetylene) TNT: trinitrate (Baidu) based (Baidu) methyl (Baidu) phenylethanol, ethanol: C2H5OH chlorofluorocarbon: it is a good refrigerant and toxic. But it destroyed the O3 layer. Acetic acid: glacial acetic acid and vinegar. Components of cracking gas (petroleum cracking): olefins, alkanes, alkynes, H2S, CO2, CO, etc. Glycerol, glycerol: C3H8O3 Coke oven gas components (coal dry distillation): H2, CH4, ethylene, CO and other carbonic acids: phenol formaldehyde: formaldehyde HCHO formalin: 35%-40% formaldehyde aqueous solution formic acid: formic acid HCOOH glucose: C6H 12O6 fructose: C6H 12O6 sucrose: C. Starch: (C6H 10O5)n stearic acid: C 17H35COOH oleic acid: C 17H33COOH palmitic acid: C 15H3 1COOH oxalic acid: oxalic acid HOOC—COOH makes the ink color blue and strong. Fading potassium permanganate solution. 2009-9- 15 17:50 reply. Listen to Hu on the second floor 169 fans. 2. Colored iron: Iron powder is black; A piece of solid iron is silvery white. Fe2+- light green fe3o 4- black crystal Fe(OH)2- white precipitate Fe3+- yellow Fe(OH)3- reddish brown precipitate Fe(SCN)3- blood red solution FeO- black powder Fe (NH4)2(SO4). 2- light blue green fe2o 3- reddish brown powder FeS- black solid copper: simple substance is purplish red Cu2+- blue CuO- black Cu2O- red CuSO4 (anhydrous)-white CuSO4 5h2o-blue Cu2(OH)2c O3- green Cu(OH)2- blue [Cu(NH3)so 4- dark blue solution BaSO4 and BAC. AgCl, Mg (OH)2 and tribromophenol are all white precipitated Al(OH)3, white flocculent precipitated H4SiO4 (orthosilicic acid), white colloidal precipitated Cl2, HCl, HBr and HI are all colorless gases, and all of them form white mist CCl4-a colorless liquid with higher density than water, which is insoluble in water-KMnO4-purple MnO4-purple. Toxic gas solid colorless solid (boiling point 44.8°c) magenta solution-red hydrofluoric acid: HF-corrosive glass N2O4, NO-colorless gas NO2- reddish brown gas NH3-colorless irritating gas 2009-9-1517: 56544. 2.Na reacts with H2O (with phenolphthalein), melts, floats on the water surface, rotates and releases gas; (melting, floating, swimming, hissing, red) 3. Flame reaction: Na yellow, K purple (blue cobalt glass), Cu green, Ca brick red, Na+ (yellow), K+ (purple). 4. Copper wire burns in Cl2 to produce brown smoke; 5. The combustion of H2 in Cl 2 is a pale flame; 6. The combustion of sodium in chlorine produces a lot of white smoke; 7. The combustion of P in Cl2 produces a lot of white smoke; 8. firstly, SO2 is introduced into the magenta solution to fade, and then the magenta solution is heated to restore its original color; 9, NH3 and HCl meet to produce a lot of white smoke; 10, aluminum foil burns violently in oxygen to produce dazzling white light; 1 1, magnesium bars produce dazzling white light when burned in air, and white powder (MgO) and black smoke when burned in CO2; 12, iron wire burns in Cl2, producing brown smoke; 13, HF corrodes glass: 4HF+SiO2 = SiF4+2H2O 14, and Fe(OH)2 is oxidized in air: from white to grayish green and finally to reddish brown; 15, at room temperature: Fe and Al are passivated in concentrated H2SO4 and HNO3; 16, dropping FeCl3 solution into a test tube containing phenol solution, and the solution is purple; Phenol turns pink when exposed to air. 17, protein turns yellow in concentrated nitric acid, and has the smell of burnt feathers when burning. 18. Burning in air: S- weak light blue flame H2- light blue flame H2S- light blue flame CO blue flame CH4- bright blue flame S burning in O2-bright blue-purple flame. 19. Characteristic reaction phenomenon: 20. Pale yellow solid: s or Na2O2 or AgBr 2 1. Make.

6. Urgent use: A common chemical problem: when taking solid drugs, "one inclination, two exemptions and three rectifications" and

"One, Two, Three" in Chemical Experiment Operation 1 When taking solid powder in the laboratory, it should be "one oblique, two conveying and three vertical". Even if the test tube is tilted, carefully hand the medicine spoon containing medicine to the bottom of the test tube, then erect the test tube and let all the medicine fall to the bottom of the test tube. 2. When taking solid or metal particles in the laboratory, it should be "one horizontal and two vertical" and then slowly erect the container, so that the drug or metal particles can slowly slide to the bottom of the container to prevent the container from breaking. 3. Pay attention to "one stick, two lows and three leanings" in liquid filtration operation, that is, the filter paper should be close to the inner wall of the funnel, the edge of the filter paper should be lower than the edge of the filter paper, the liquid level in the funnel should be lower than the edge of the filter paper, the beaker should be close to the glass rod, and the end of the glass rod should gently lean against one side of the three-layer filter paper and the nozzle at the lower end of the funnel. Don't put your nostrils close to the mouth of the container to smell the smell; Don't taste any medicine. (2) Preservation: Take the medicine in strict accordance with the dose specified in the experiment. If there is no prescribed dose, the minimum dose is generally taken, and the bottom of the test tube only needs to be covered for solid medicine, and 1.2ml is taken for liquid. (3) Remaining drugs: Don't put them back in the original bottle, don't throw them away at will, and don't take them out of the laboratory. It should be put in a designated container. 2. Access to solid drugs (1) Solid drugs should be stored in wide-mouth bottles. (2) Powdered drugs or small particles of drugs should be taken with a spoon, and the drugs should be sent to the bottom of the test tube with a paper slot. After use, take out the block medicine with tweezers, put it into the flat test tube mouth, and then slowly erect the test tube (one horizontal, two horizontal, three horizontal and three slow delivery).