1. Chemistry common sense in daily life
Chemistry common sense in daily life 1. Looking for chemistry common sense 100 common sense about chemistry in daily life
1. Chemistry The most abundant 1. The most abundant metallic element in the earth's crust is aluminum. 2. The most abundant non-metallic element in the earth's crust is oxygen. 3. The most abundant substance in the air is nitrogen. 4. The hardest naturally occurring substance is diamond. 5 . The simplest organic matter is methane. 6. The most mobile metal in the metal activity sequence is potassium. 7. The oxide with the smallest relative molecular mass is water. 8. The gas with the smallest density under the same conditions is hydrogen. 9. The most conductive metal is silver. 10. The atom with the smallest relative atomic mass is hydrogen. 11. The metal with the smallest melting point is mercury. 12. The most abundant element in the human body is oxygen. 13. The element that makes up the most types of compounds is carbon. . 14. The most widely used metal in daily life is iron. 2. Fill in the blanks 1. The three types of particles that constitute matter are molecules, atoms, and ions. 2. The three reducing agents commonly used to reduce copper oxide are hydrogen, carbon monoxide, and carbon. 3. , Hydrogen has three major advantages as a fuel: rich resources, high calorific value, and the product after combustion is water and does not pollute the environment. 4. There are generally three types of particles that make up atoms: protons, neutrons, and electrons. 5. There are only three types of ferrous metals: iron , manganese, chromium. 6. The elements that constitute matter can be divided into three categories: (1) metallic elements, (2) non-metallic elements, (3) rare gas elements. 7. There are three types of iron oxides, and their chemical formula is ( 1) FeO, (2) Fe2O3, (3) Fe3O4.8, the solution has three characteristics (1) homogeneity; (2) stability; (3) mixture. 9. The chemical equation has three meanings: (1) Expression What substances participate in the reaction and what substances are produced as a result; (2) Indicates the ratio of the number of molecules or atoms of each substance in the reactants and products; (3) Indicates the mass ratio between the reactants and products. The chemical equation is Two principles: based on objective facts; follow the law of conservation of quality. 10. Pig iron is generally divided into three types: white iron, gray iron, and ductile iron. 11. Carbon steel can be divided into three types: high carbon steel, Medium carbon steel, low carbon steel. 12. There are three types of iron ores commonly used in ironmaking: (1) Hematite (main component is Fe2O3); (2) Magnetite (Fe3O4); (3) Siderite (FeCO3). 13. There are three main equipments for steelmaking: converter, electric furnace, and open hearth. 14. The three reaction conditions that are often related to temperature are ignition, heating, and high temperature. 15. There are two ways to change a saturated solution into an unsaturated solution. : (1) Raise temperature, (2) Add solvent; there are three ways to change an unsaturated solution into a saturated solution: cooling down, adding solute, and evaporating the solvent at a constant temperature. (Note: Substances whose solubility decreases with temperature, such as calcium hydroxide solution, change from saturated solution to saturated solution. The solution becomes an unsaturated solution: cooling down, adding solvent; there are three ways to change an unsaturated solution into a saturated solution: raising the temperature, adding solute, and evaporating the solvent at a constant temperature). 16. There are generally three methods for collecting gas: drainage method, upward emptying method, and downward Evacuation method. 17. Three main causes of water pollution: (1) Waste residue, waste gas, and waste water in industrial production; (2) Random discharge of domestic sewage; (3) Pesticides and fertilizers used in agricultural production flow in with rainwater Hezhong. 18. There are three types of fire extinguishers commonly used: foam fire extinguishers; dry powder fire extinguishers; liquid carbon dioxide fire extinguishers. 19. The solubility of solid substances changes with temperature can be divided into three categories: (1) The solubility of most solid substances increases with temperature. It increases with increasing temperature; (2) The solubility of a few substances is very little affected by temperature; (3) The solubility of a very few substances decreases with the increase of temperature. 20. There are three reasons why CO2 can extinguish fires: it cannot burn and it cannot support combustion. , Denser than air. 21. Elemental substances can be divided into three categories: metallic elements; non-metallic elements; rare gas elements. 22. The three most important fossil fuels in the world today are: coal, oil, and natural gas. 23. It should be noted The three black oxides living in the environment are: copper oxide, manganese dioxide, and ferric oxide. 24. Hydrogen and carbon elements have three similar chemical properties: stability at room temperature, flammability, and reducibility. 25. In the textbook Three times light blue appears: (1) Liquid oxygen is light blue (2) Sulfur is in the air
There is a weak light blue flame burning in the air. (3) Hydrogen burning in the air has a light blue flame. 26. Three blue colors related to the copper element: (1) copper sulfate crystal; (2) copper hydroxide Precipitation; (3) Copper sulfate solution. 27. There are "three supports" in the filtration operation: (1) The lower end of the funnel is close to the inner wall of the beaker; (2) The end of the glass rod rests lightly on the third layer of the filter paper; (3) Wait for The edge of the beaker of filtrate is close to the glass holder for drainage. 28. The Kip generator consists of three parts: a spherical funnel, a container, and an air guide. 29. The flame of an alcohol lamp is divided into three parts: outer flame, inner flame, and flame core. , among which the outer flame temperature is the highest. 30. When taking medicines, there are "three no's" principles: (1) Do not touch the medicines with your hands; (2) Do not put your nose to the mouth of the container to smell the gas; (3) Do not taste the medicines .31. Write the color and state of the following substances: Bile alum (blue alum, copper sulfate pentahydrate CuSO4?5H2O): blue solid basic copper carbonate (patina): green solid black solid: carbon powder, copper oxide, dioxide Manganese, ferric oxide white solid: anhydrous copper sulfate (CuSO4), potassium chlorate, potassium chloride, magnesium oxide, sodium chloride, calcium carbonate, sodium carbonate, zinc sulfate Purple black: potassium permanganate light green solution: sulfuric acid Ferrous iron (FeSO4) 32. The conditions for burning combustibles: the combustibles are in contact with oxygen, and the temperature of the combustibles must reach the ignition point. 33. Gases with molecules composed of diatomic atoms: H2, O2, N2, Cl2, F234, The following are determined by which part of the atomic structure: ①. The type of element is determined by the number of protons. ②. The classification of elements is determined by the number of electrons in the outermost shell. ③. The chemical properties of the element are determined by the number of electrons in the outermost shell. ④. The valence is determined by the number of electrons in the outermost shell. ⑤. The relative atomic weight is determined by the number of protons and neutrons. 35. Organic compounds learned: CH4 (methane), C2H5OH (alcohol, ethanol), CH3OH (methanol), CH3COOH (acetic acid, acetic acid) ) 36. Understanding the law of conservation of mass from a macro and micro perspective can be summarized into five constants, two certain changes, and one possible change: (1) Five constants: Look at the types of elements and the relationship between reactants and products at the macro level. The total mass remains unchanged, and the atomic mass, atomic type and number of atoms remain unchanged when viewed from a microscopic perspective; (2) Two certain changes: the type of matter must change when viewed from a macroscopic perspective, and the type of molecules must change when viewed from a microscopic perspective; (3) One possible change : The sum of molecules may change. 37. Two simple substances of carbon: graphite and diamond (the reason for their formation: the arrangement of carbon atoms is different). 38. Write the following substances.
2. Chemistry tips in daily life
1. Use of iodized salt.
Iodine is an essential nutrient for the human body. Long-term iodine deficiency can lead to iodine deficiency. Consuming iodized salt is the simplest, most economical and effective way to eliminate iodine deficiency. Iodized table salt contains sodium chloride and potassium iodate. The iodine needed by the human body is provided by potassium iodate. However, potassium iodate is unstable and easy to decompose when exposed to heat and light, thus affecting the body's intake of iodine, so when cooking Note: Add salt when it is almost out of the pot, and do not stew for a long time.
2. Do not cook tofu and spinach together. Calcium oxalate is a precipitate that cannot be absorbed by the human body.
Spinach, onions, and bamboo shoots are rich in oxalic acid and sodium oxalate, and tofu contains more calcium salts, such as calcium sulfate and other ingredients. The above substances can undergo a metathesis reaction to generate calcium oxalate precipitation and other substances.
From a medical point of view: spinach, onions, bamboo shoots, etc. should not be mixed with tofu at the same time, as they will produce calcium oxalate precipitation, which is an inducement to produce stones; from a nutritional point of view, mixed consumption will destroy the Their nutritional content. 3. The harm of aluminum to human health.
Aluminum has always been considered a non-toxic element, so aluminum drinking utensils, aluminum-containing leavening agent baking powder, water purifiers, etc. are widely used. However, research in recent years has shown that aluminum can disrupt the metabolism of the human body and slowly cause harm to human health over a long period of time. The toxicity caused by it is slow and difficult to detect. However, once the toxic reaction of metabolic disorder occurs, the consequences will be serious.
To prevent aluminum poisoning, you should pay attention to (1) Reduce the entrance route of aluminum, such as eating less fried dough sticks, and try to avoid aluminum hydroxide when using drugs to treat the stomach.
(2) Eat less food packaged in aluminum products.
(3) Use aluminum products sparingly and avoid prolonged contact between food or drinking water and aluminum products. 4. Why fruits can relieve hangover? This is because fruits contain organic acids. For example, apples contain malic acid, citrus contains citric acid, grapes contain tartaric acid, etc. The main component of wine is ethanol. Organic acids can It interacts with ethanol to form esters to relieve hangover.
In the same way, vinegar can also relieve hangovers because vinegar contains 3-5 acetic acid. Acetic acid can esterify with ethanol to form ethyl acetate. 5. It is not advisable to burn the oil until it smokes when cooking. When the oil is at high temperature, it is easy to form a polycyclic compound. Generally, vegetable oil contains a lot of unsaturated fatty acids, which makes it easier to form polycyclic compounds. Experiments have proved that polycyclic compounds are easy to induce animal diseases. Get bladder cancer.
Generally, just burn the oil until it boils, and the "anger" of the oil can be removed. 6. Why do “red tides” appear in seawater?
In recent years, large areas of red tide have appeared in offshore waters such as Bohai Bay in my country. People call this phenomenon "red tide." Red tide is not a tidal phenomenon, nor is it a movement of ocean currents like the "black tide", but a biological phenomenon in which red plankton overproduces under specific conditions in the ocean.
Why can plankton overproduce? It turns out that a large amount of wastewater, waste residues and substances entering the ocean through atmospheric exchange contain nitrogen, phosphorus and other elements, which are essential nutrients for plant growth. As a result, plankton multiply rapidly, causing the sea to wear a "red dress."
In order to prevent the phenomenon of marine red tide, the discharge of nitrogen- and phosphorus-containing wastes, such as phosphorus-containing laundry detergent wastewater, into the ocean should be controlled to maintain the ecological balance in the ocean. 7. The acidity and alkalinity of food.
Studies have found that eating more alkaline foods can keep the blood weakly alkaline, reduce acidic substances such as lactic acid and urea in the blood, and prevent their deposition on the blood vessel walls, thus softening the blood vessels. , so some people call alkaline foods "cleaners for blood and blood vessels." Generally speaking, foods such as rice, flour, meat, fish, and eggs are almost all acidic foods, while vegetables, fruits, milk, potatoes, potatoes, soy products, and aquatic products are all alkaline foods.
By paying attention to a scientific diet, improving food structure, strengthening physical exercise, and developing good living habits, vascular sclerosis can be delayed and reversed. The pH of human body fluids is closely related to IQ level.
Within the allowable range of the pH of body fluids, those with higher acidity will have lower IQs, and those with higher alkalinity will have higher IQs. Scientists tested dozens of boys aged 6 to 13, and the results showed that children with a pH value of body fluid in the cerebral cortex greater than 7.0 had IQs that were twice as high as those with a pH value less than 7.0.
Some children with poor academic performance and low intellectual development often have acidic constitutions. 8. Sulfur dioxide in food.
Sulfur dioxide is an important member of inorganic chemical preservatives. Sulfur dioxide has been used as a food additive for centuries. The earliest recorded use was in the Roman era when it was used to sterilize wine vessels.
Later, it was widely used in food, such as sulfur fumigation in the manufacture of dried fruits and preserved fruits; it was made into a sulfur dioxide sustained-release agent for the preservation and storage of grapes and other fruits. Sulfur dioxide can show a variety of technical effects in food. It is generally called a bleaching agent because sulfur dioxide can react with colored substances to bleach food.
On the other hand, sulfur dioxide has a reducing effect and can inhibit the activity of oxidase, thereby inhibiting enzymatic browning. In short, because the application of sulfur dioxide can make dried fruits, preserved fruits, etc. have a beautiful appearance, some people call it a cosmetic additive.
While sulfur dioxide plays a "cosmetic" role, it also has many non-cosmetic functions, such as antisepsis and antioxidant, which are necessary to maintain the nutritional value and quality of food. For a long time, people have believed that sulfur dioxide is harmless to the human body. However, since Baker et al. discovered in 1981 that sulfite can induce asthma relapse in some asthma patients, people have re-examined the safety of sulfur dioxide.
After long-term toxicological studies, it is believed that sulfite preparations have no obvious harm to most people at the current dosage. Two other points should be noted: The sulfites in food must reach a certain dose to cause allergies. Even those who are very sensitive to sulfites are not allergic to all foods treated with sulfites. , from this point of view, sulfur dioxide is a relatively safe preservative.
9. Why does table salt deliquesce? How to keep it from deliquescing? Magnesium chloride is often found in table salt. Magnesium chloride deliquesces in the air.
In order to prevent the deliquescence of the salt, the salt can generally be dry-fried in a pot. Since magnesium chloride is completely hydrolyzed at high temperatures to form magnesium oxide (MgO), it loses its deliquescent property.
Or purify the table salt. Pure sodium chloride is not found in the air.
3. Common knowledge about chemistry ~ help me answer 20 common sense about chemistry
Don’t put spinach and tofu together in cooking. The vitamin content of spinach is different. It is among the best in growing vegetables. One pound of spinach contains approximately 133 grams of carotene (the raw material for producing vitamin A) and 138 grams of vitamin C, which is more than double the content of the well-known tomatoes.
Therefore, eating spinach regularly is very good for health, and it also has good effects on anemia, hypertension, rickets and tooth bleeding. Spinach contains a lot of oxalic acid and is not suitable for cooking with tofu.
When magnesium chloride (brine MgCI2) or gypsum (CaSO4) in tofu meets oxalic acid, a chemical reaction occurs, producing magnesium oxalate or calcium oxalate that is insoluble in water, and is deposited on the blood vessel wall, affecting the blood vessel wall. Blood circulation, which has a particularly great impact on the normal development of children. The oxalic acid in spinach also affects children's absorption of calcium.
However, this shortcoming of spinach can be remedied. Just wash the spinach with hot water and then soak it in cold water for about 20 minutes, so that most of the oxalic acid will be leached out. 2.
Is boiler water drinkable? The water used for steaming steamed buns or side dishes at home is called steamer water. This kind of steamer water cannot be drunk, nor can it be used to cook rice or porridge. Why is this? We know that water contains trace amounts of nitrate. When the water is heated for a long time, the concentration of nitrate increases relatively due to the continuous evaporation of water, and it decomposes into nitrite when heated.
Nitrite is extremely harmful to people's health. It can denature the hemoglobin in human blood so that it can no longer combine with oxygen, leading to early hypoxia.
Nitrite can also lower blood pressure in the human body and can cause collapse in severe cases. Modern medicine has proven that nitrite is also a strong carcinogen.
Therefore, you cannot drink the steamer water. 3.
When people buy mutton, they often judge the freshness of the meat based on its color. Why? Due to incomplete bleeding when slaughtering pigs and sheep, heme remains. The iron in the heme exists in the form of divalent ions, so the fresh meat is bright red. As the meat ages, the divalent iron ions are gradually oxidized into trivalent iron ions by the air, making the meat appear dark red.
4. 10 kinds of food should not be eaten too much. Preserved eggs: A certain amount of lead is needed to make preserved eggs. Therefore, eating too much can cause lead poisoning and calcium deficiency.
Stinky tofu: Stinky tofu is easily contaminated by microorganisms during the fermentation process. It also contains a large amount of volatile base nitrogen and hydrogen sulfide. These are putrefactive substances caused by protein decomposition. Eating too much is harmful to the human body. MSG: The intake of MSG per person per day should not exceed 6 mg. Excessive intake will increase the content of glutamate in the blood, limit the use of necessary divalent cations calcium and magnesium, and may cause short-term headaches, nausea, etc. Symptoms can also have adverse effects on the human reproductive system.
Instant noodles: Instant noodles contain food colorings and preservatives that are harmful to the human body. Regular consumption of instant noodles is not good for the body. Sunflower seeds: Sunflower seeds contain unsaturated fatty acids. Eating too much will consume a large amount of alkali in the body and affect the function of liver cells.
Spinach: Spinach is rich in nutrients, but it contains oxalic acid. The zinc and calcium in food will combine with oxalic acid and be excreted from the body, causing zinc and calcium deficiency in the human body. Pork liver: 1,000 grams of pork liver contains more than 400 mg of cholesterol. Too much cholesterol intake by a person can cause arteriosclerosis and aggravate cardiovascular disease.
Roast beef and mutton: Harmful substances such as benzopyrene are produced during the roasting process of beef and mutton, which are cancer-causing substances. Pickled vegetables: If pickled vegetables are not pickled well, they will contain carcinogen nitrite amines.
Fried dough sticks: The alum in fried dough sticks is an inorganic substance containing aluminum. If you eat fried dough sticks every day, it will be difficult for the aluminum to be excreted by the kidneys, which will poison the brain and nerve cells and even cause Alzheimer's disease. Regular consumption of detoxifying foods is good for your health. Pig blood: Traditional Chinese medicine believes that pig blood is beneficial to defecation and removes intestinal dirt.
Modern medicine has confirmed that after the plasma protein in pig blood is decomposed by gastric acid in the human body, it can produce a detoxifying and intestinal-cleansing decomposition product. This substance can interact with dust and harmful metals that invade the human body. The particles undergo a biochemical reaction and are then excreted from the digestive tract. Kelp: Traditional Chinese medicine believes that kelp is cold in nature and salty in taste, and has the functions of softening and dispersing stagnation, clearing away heat and diuresis, removing fat and lowering blood pressure.
Kelp also has the effect of preventing leukemia (blood cancer). Carrots: Carrots are also effective detoxifiers.
Not only is it rich in carotene, which can increase vitamin A in the human body after eating, but it also contains a large amount of pectin. This substance combines with mercury to effectively reduce the concentration of mercury in the blood and accelerate the elimination of mercury in the body. The elimination of ions, so it has the effect of driving away mercury. 5.
The color, aroma and taste of food. The color of food is mostly artificial coloring, and food coloring is added during production. The color of some foods is due to the fact that they contain certain natural pigments.
For example, the green color shown in the stems and leaves of vegetables and immature fruits is chlorophyll, the red color in tomatoes is tomato pigment, and the shells of shrimps and crabs contain leucophyllin, which can turn red when exposed to heat. The aroma of food comes from volatile substances such as alcohols, aldehydes, ketones, and esters.
Fish, meat, and eggs are rich in protein. The protein itself has no umami taste, but after being cooked, it is hydrolyzed into a variety of amino acids, and the amino acids have a delicious taste. Among amino acids, glutamic acid has the most delicious taste.
"MSG" is the sodium salt of glutamic acid. When sucrose is diluted to 200 times with water, the sweetness will no longer be felt, while when MSG is diluted to 3,000 times with water, you can still taste the umami flavor! Recently, a powerful MSG made from a mixture of sodium glutamate and sodium inosinate has been developed. Its umami flavor is 40 times that of MSG.
Shrimps, crabs, snails, and clams contain a lot of succinic acid, so they have a unique umami flavor that is loved by people. The aroma of cinnamon is due to the presence of cinnamaldehyde, while the aroma of koji wine comes from the fusel alcohols and esters produced during the fermentation process.
The aroma of bananas comes from the volatile isoamyl acetate, and the aroma of citrus comes from the nerolidol contained. As for the aroma of pastries and candies, it is due to the addition of artificial fruit flavors.
In our country, people are accustomed to dividing taste into "five flavors": sour, sweet, bitter, spicy, and salty. The sour taste is caused by the hydrogen ions ionized by various organic acids. The strength of the sour taste depends on the concentration of hydrogen ions.
Vinegar contains about 3-5 acetic acid, sauerkraut contains lactic acid, and the sourness in fruits, drinks or candies comes from its citric acid, tartaric acid, malic acid and vitamin C. . Sweetness is caused by sugars such as sucrose, fructose, glucose, maltose, and lactose.
When making pastries, biscuits, popsicles, and ice cream, an appropriate amount of saccharin is often added.
4. Some little chemistry knowledge in life
1. Four major categories of biological macromolecules: 1. Sugar, a thing commonly known as "carbohydrate".
2. Protein, a model macromolecule made of amino acids. It's a pity that human protein can only be built from 20 kinds of lovely amino acids, 8 of which need to be taken in from the outside.
3. Lipid, an energy-based biological macromolecule that makes modern women vomit.
4. Nucleic acid, an important substance said to affect heredity.
Biologists all over the world are spinning their heads around DNA and RNA. The constituent elements of all these substances are simple C, H, O, N, P, S. Their Chinese characters should not be forgotten.
2. Inorganic materials have a great relationship with our lives. 1. Obviously, the main component of our stainless steel pot is iron.
The reason why it is rust-free and wear-resistant is because steel-making workers added the nasty metal chromium (Cr) to it. 2. As for nanomaterials, in comparison, their surface area is much larger, and they have super strong optical, electrical, magnetic, and thermal properties.
Also, don’t forget, 1 nanometer = 1*10-9 meters. 3. Of course, the metal with the highest melting point is the tungsten filament in my light bulb; the lowest is the mercury in the thermometer; the metal with the hardest melting point is chromium in the stainless steel pot; gold has always been proud of having the best ductility; silver also conducts electricity It is favored by scientists because of its good properties; lithium is the lightest metal, compared with osmium (Os), which has a higher specific gravity.
4. Quartz optical fiber is a good thing, generally used for communication and medical treatment. Specifically, it uses the high refractive index of SiO2 to transmit information and penetrate the internal organs ("gastroscope"). 5. So, what exactly is a shape memory alloy? It turns out that after being deformed, it will return to its original shape when heated to a certain temperature.
What a wonderful world! 6. Of course, if we arrange soda glass, potassium glass, quartz glass, FRP and tempered glass, we will find that FRP is the one that can withstand pressure and tension, and quartz glass is the one that can withstand high temperatures and sudden cooling and heating. Other glasses are too squeamish and not a good boy.
3. Environmental pollution 1. Pollution incidents that shocked the world: Maas Valley smog incident (Belgium); Los Angeles photochemical smog; Donora smog incident (Pennsylvania, USA); London smog incident; Minamata (yu ) disease incident (Japan); bone pain incident (Japan); Yokkaichi asthma incident (poor Japan again); rice bran incident (Japan); Pabol incident (India); Chernobyl nuclear leakage incident (Soviet Union ); Rhine River pollution incident (Switzerland); ocean and air pollution incident during the Gulf War. 2. As for what the "atmospheric temperature inversion phenomenon" and the stratification of the atmosphere are, we will not record them here due to limited space.
3. The main components of automobile exhaust: CO, NOx, SO2, HC (hydrocarbons) and solid particles (lead compounds, carbon particles, oil mist, etc.). It is these things that bring audible and invisible suffering to our cities.
4. Dust particles in the atmosphere: ⅰ. Falling dust: diameter is greater than 10 microns, can fall by gravity, and the harm to human body is barely tolerable; ⅱ. floating dust: diameter is less than 10 microns, in the air Wandering for a long time has caused many elderly people and children to die of lung disease, and it is chronic - an invisible ghost killer! 5. Definition of photochemical smog: Nitrogen oxides, hydrocarbons and other primary pollutants undergo a series of photochemical reactions under the action of sunlight's ultraviolet rays, generating ozone (accounting for more than 85% of the products), peroxyacetyl nitrate, highly reactive free radicals, aldehydes Secondary pollutants such as steroids, ketones and organic acids. The mixture of these primary pollutants and secondary pollutants is called photochemical smog. IV. Chemical elements and human health. Anyone who does not believe it is going against the trend of history. 1. Common trace elements: vanadium V, chromium Cr, manganese Mn, iron Fe, cobalt Co, nickel Ni, copper Cu, zinc Zn, molybdenum Mo, iodine Z, selenium Se, tin Sn, silicon Si, bromine Br, fluorine F. Boron B.
(Major elements are carbon, hydrogen, oxygen, and nitrogen that are indestructible) 2. Harmful elements: lead Pb, mercury Hg, chromium Cr6, beryllium Be, cadmium Cd, arsenic As3 5. High oxidation in the shadow of modern life Molecular materials 1. The most prominent feature of the so-called polymer compound is its "high" molecular weight. Generally, it must be above 10,000 to be called a polymer. Of course it is an organic compound, that is, it contains carbon.
2. So what are polymer materials? It refers to a wonderful material made from polymers as basic raw materials, adding appropriate auxiliaries, and undergoing certain careful processing. 3. According to their uses, polymer materials can be divided into plastics, rubber, fibers, coatings, adhesives, sealing materials, etc., all of which are emitting light and heat in the construction of the national economy.
6. There is a close relationship between viruses and health 1. Common antiviral drugs: amantadine, methylamantadine, vidarabine, ribavirin, and acyclovir , ganciclovir, zidovudine, virus spirit. 2. Viral interference phenomenon: This is the philosophy of vicious people, that is, two viruses infect the same cell, and a wonderful phenomenon occurs where one virus inhibits the increase of the other virus.
As the saying goes, "There is always a black hand in the darkness, and there is a wind coming from outside the sky." 3. Be sure to remember that the virus is not resistant to cold or heat, a typical Siberian spirit.
7. Ozone and Ozone Layer Depletion Ozone is confined to the stratosphere in an area of ??15-35 kilometers. This is an indisputable fact.
8. The "radiation" of radiation chemistry on ordinary people's lives 1. Ionizing radiation: radiation with energy greater than the ionization energy of atoms (molecules) (about 5-25 radiation eV), they act on matter When doing so, atoms (molecules) are often forced to ionize or become excited - even if they are unwilling to do so. 2. Radiation chemistry: A branch of chemistry that studies the chemical effects produced when ionizing radiation interacts with matter.
According to data, Beijing Normal University is doing very well in this field. 3. Absorbed dose and unit: The energy absorbed by the unit mass of the illuminated substance is called absorbed dose.
Its SI unit is J.kg-1, euphemistically called "Gy". 1Gy equals 1J of energy absorbed by 1kg of irradiated material.
That is, 1Gy=1 J.kg-1 1Gy=100racl This is stipulated by troubled people and does not require a reason. 9. Unsaturated fatty acids and human health 1. Fatty acids, which are mainly composed of carbon, hydrogen and oxygen, are the most critical material basis of fat; even the most critical material basis of health is fatty acid.
2. ω-3 series: fish oil, α-linolenic acid; ω-6 series: γ-linolenic acid, linoleic acid, arachidonic acid; ω-9 series: oleic acid. In fact, these.
5. Chemistry is everywhere in life. Xiaoqiang uses the chemical knowledge he learned in life and conducts the following explorations
(Small) Since calcium carbonate can react with acid, Xiaoqiang should start from The kitchen chooses eggs and acetic acid; (5) ① If salt powder is gradually added to the cup until the solution is saturated, since the density of saturated salt water is greater than the density of eggs, the buoyancy force on the eggs gradually becomes greater than gravity, and the eggs will float; ② Due to the eggshell The main ingredient is calcium carbonate. Add concentrated hydrochloric acid to the beaker. The reaction of O1 5H l═a l5 H5O O5↑ will occur. Therefore, bubbles will be generated on the surface of the egg shell, and the generated carbon dioxide gas will be attached to the The surface of the egg makes the egg float first, and when it reaches the top of the solution, the bubbles decrease, the gravity is greater than the buoyancy, and it sinks again. It keeps floating up and down, and finally floats up; (1) ① Because calcium carbonate, the main component of the egg shell, can react with hydrochloric acid to generate carbon dioxide gas , Carbon dioxide does not support combustion and cannot burn, and under the same conditions, it is denser than air, which will cause the candle to extinguish; and one of the main uses determined by this property is to extinguish fire; ② When the candle is extinguished, quickly cover the mouth of the glass with a block When using a glass piece dipped in lime water, the observed phenomenon is that the lime water becomes turbid; since it cannot be proven whether the carbon element is produced by the burning of candles or by the reaction of a's O1 and hydrochloric acid, it cannot be determined; (4) Due to the oxidation of carbon dioxide and hydrogen The calcium carbonate generated by the reaction of calcium can block the pores of eggs, prevent the entry of bacteria, and play a role in preservation. The reaction equation is: a(OH)5 of O5 = O1 of a↓ H5O. Therefore, the answer is : (Small) Acetic acid; (5) ① Eggs will float. Since the density of saturated salt water is greater than the density of eggs, the buoyancy force on eggs is gradually greater than gravity; ② Bubbles will be generated on the surface of the egg shell. It will continue to float up and down, and finally float up. O1 of a 5H of l═ of a l5 of H5O O5↑, (1) ① The candle is extinguished, carbon dioxide does not support combustion and cannot burn, and the density is greater than air under the same conditions, extinguish the fire; ② The lime water becomes turbid and cannot , it is impossible to prove whether the carbon element is produced by the burning of candles or the reaction of O1 of a with hydrochloric acid; (4) a(OH)5 of O5 = O1 of a↓ H5O.