The crystal structure unit cell is a face-centered cubic unit cell.
Relative atomic mass 207.2
Element type metal element
A silvery white heavy metal with bluish physical properties, melting point of 327.502℃, boiling point of 1740℃, density of 1 1.3437 g/cm3, hardness of 1.5, soft texture and low tensile strength.
Atomic volume 18. 17 cm3/mol.
The element content in the sun is 0.0 1ppm.
The element content in the surface seawater of the Pacific Ocean is 0.0000 1ppm.
Lead oxide +2, lead +4
Lattice parameters
a = 495.08 pm
b = 495.08 pm
c = 495.08 pm
α = 90
β = 90
γ = 90
Mohs hardness 1.5
The speed of sound propagation in it is 1 190 m/s.
Ionization energy (kJ/mol)
M - M+ 7 15.5
M+ - M2+ 1450.4
M2+ - M3+ 308 1.5
M3+ - M4+ 4083
M4+ - M5+ 6640
M5+ wing M6+ 8 100
M6+ - M7+ 9 100
M7+ - M8+ 1 1800
M8+ - M9+ 13700
M9+ - M 10+ 16700
The discovery process was discovered by humans as early as around 3000 BC.
The first ionization energy described by the element is 7.4 16 eV. The second ionization energy is 15.874 eV. The melting point is 327.5℃ and the boiling point is 1740℃. The density is13.34g/cm3. Silver-gray heavy metal, soft, weak ductility and strong ductility. In the air, the surface is easy to oxidize, lose luster and become gloomy. Soluble in nitric acid, hot sulfuric acid, organic acid and lye. Insoluble in dilute acid and sulfuric acid. Amphoteric: It can form both metal salts of high lead acid and lead salts of acid.
The sources of elements mainly exist in galena (PbS) and galena (PbCO3). Calcine to obtain lead sulfate and lead oxide, and then reducing to obtain metallic lead.
Components are mainly used as cables, batteries, casting alloys, babbitt alloys, anti-X-ray materials, etc.
Element auxiliary data
Lead is a chemical element, and its chemical symbol comes from Latin. The chemical symbol is Pb (Latin lead), with an atomic weight of 207.2 and an atomic number of 82. Among all stable chemical elements, lead has the highest atomic number.
Lead is a bluish silvery white heavy metal, which is toxic and is a main group metal with ductility. Melting point 327.502℃, boiling point 1740℃, density1.3437g/cm 3, hardness 1.5, soft texture and low tensile strength.
Lead is one of the earliest metals used by human beings. In 3000 BC, people had already smelted lead from ores. The lead content in the crust is 0.00 16%, and the main ore is galena. Lead has four stable isotopes in nature: lead 204, lead 206, lead 207 and lead 208, and there are more than 20 radioactive isotopes.
Metal lead contacts with oxygen, water and carbon dioxide in the air, and its surface will be rapidly oxidized to form a protective film; When heated, lead can quickly combine with oxygen, sulfur and halogen; Lead has little effect on cold hydrochloric acid and cold sulfuric acid, but can react with hot or concentrated hydrochloric acid and sulfuric acid. Lead reacts with dilute nitric acid, but not with concentrated nitric acid; Lead will slowly dissolve in strong alkali solution.
Lead is mainly used to manufacture lead storage batteries; Lead alloy can be used for casting type and welding; Lead is also used to make protective equipment for radioactive radiation and x-rays; Lead and its compounds are toxic to human body and can accumulate in human body. Lead is used as building materials, lead acetate batteries, bullets and shells, solder, trophies and some alloys.
The content of lead in the earth's crust is very small, and there is also a small amount of natural lead in nature. However, due to the accumulation of lead-containing minerals and low melting point (328℃), lead has been used in ancient times.
Galena (PbS) is still the main source of lead extraction. In ancient times, people accidentally put ...
Question 2: What food or article contains lead for 30 minutes? Lead is a common metal, and we often use it in our daily life. So what things in our lives contain lead? Lead Futures Network summarizes for you:
(1) Soil and dust in the living environment, toys and school tools, inferior paints and printing inks for home decoration, scalding wine and drinking with lead-containing lead pots or tin pots, and abusing lead-containing pills or remedies.
(2) Lead-containing foods, some beverages, inferior foods, Chinese herbal medicines, etc. Lead in food, such as some canned food, leads to the increase of lead content in food because of lead in weld; Foods with high lead content are mainly popcorn processed in containers with high lead content, and lead oxide is added to accelerate the ripening of preserved eggs.
(3) Lead in animals and plants. The lead content of plant food is influenced by the lead content of soil, fertilizer, pesticide and irrigation water. The lead content of animal food is influenced by the lead content of feed, pasture, air and drinking water.
(4) Air pollution, such as automobile exhaust with leaded gasoline, and families with coal products (such as briquettes) as fuel, the average content of lead in indoor air is much higher than that in outdoor air.
(5) Adults and clothes exposed to lead cross-infect children. For example, traffic booths, printing houses, steel mills, refineries, foundries, battery industries and mines are all the hardest hit areas of lead pollution. Many industries have access to lead compounds. As adults, we should pay attention to the prevention of lead poisoning, not only to protect ourselves, but also to protect our children.
(6) using lead-containing glazed porcelain; Use cosmetics containing lead.
Therefore, we should always pay attention to prevent lead poisoning in our daily life.
Question 3: What foods contain lead with high lead content, mainly popcorn and preserved eggs.
Lead is a big killer of brain cells. Excessive lead content in food will damage the brain and cause mental retardation.
Some children often eat popcorn because in the process of making popcorn, after the machine can is heated by high pressure, part of the lead on the surface of the soft lead pad in the inner layer of the can cover will become gaseous lead.
In the process of making preserved eggs, raw materials contain lead oxide and lead salt. Lead has a strong penetrating power, and eating too many preserved eggs will also affect intelligence.
Pregnant women drink too much beer, and the lead in the liquid will reach the fetal brain through the placenta, which will damage intelligence.
There are many reasons for lead poisoning. Dr. Ren said that there are many reasons for lead poisoning, such as eating food containing lead, such as preserved eggs, popcorn, canned lead solder, and fruit skins. Frequent contact with color-coded food packaging, paint, lead-containing cosmetics, hair dyes, clothes contaminated with lead, automobile exhaust and lead-containing drugs; Light candles containing lead, especially scented candles and slow-burning candles. Among them, for adults who have little contact with lead, the use of unqualified colored glazed tableware may be an important reason for the excessive lead content in the body.
According to reports, heavy metals such as lead and cadmium in unqualified porcelain are easily dissolved from the beautiful glaze, causing chronic harm to human health. Ceramic tableware is usually decorated with glaze, which contains heavy metals such as lead and cadmium. When it comes to acidic food, poor quality products will have excessive lead and cadmium dissolved in the food. If people eat foods with high lead content and cadmium content for a long time, it will lead to the deposition of lead in the blood, leading to the damage of the central nervous system of organs such as the brain and kidneys. In-glaze and under-glaze colored ceramics with smooth surfaces like glass have little or no lead and cadmium dissolution, so you can buy them with confidence. For glazed products with uneven surface, try to choose products with less decorative patterns on the surface. For those products that are not at ease, you can soak them in vinegar for several hours. If there are obvious color changes, they should be discarded.
To prevent lead poisoning in many ways, we should start with diet, living habits and other aspects. First of all, printed materials such as newspapers should not be used as food packaging in the diet. When food is packed in food bags, direct contact with food, especially acidic food, should be avoided. Wash vegetables and fruits before eating, and peel them as much as possible to prevent pesticide residues of lead.
In terms of living, try not to use lead-containing paint to decorate the walls, floors and furniture at home, otherwise once the paint crumbs peel off, the lead in the paint will easily cause lead pollution in the living room. Try to use lead-free cosmetics, hair dyes, etc.
In addition, don't walk near roads with many cars, because automobile exhaust and soil around roads contain a lot of lead.
Diet should contain enough high-quality protein, such as eggs, lean meat, poultry, fish and shrimp, soybeans, bean products, etc., accounting for more than 1/2. Foods rich in vitamins, especially vitamin C, should be selected in dietary distribution. Appropriate vitamin C supplementation can not only make up for the consumption of vitamin C by lead, but also slow down the symptoms of lead poisoning. Vitamin C can also combine with lead in the intestine to form lead ascorbate with low solubility, which reduces the absorption of lead. At the same time, vitamin C also directly or indirectly participates in the detoxification process and promotes the discharge of lead. Appropriate vitamin E supplementation can resist the peroxide reaction caused by lead, while vitamin D supplementation can affect the absorption and deposition of lead by regulating calcium and phosphorus. Supplementing vitamins b 1, b2, b6, b 12 and folic acid can also improve symptoms and promote the recovery of physiological functions.
Eat some lead-free food properly. Many natural foods have certain functions of preventing and expelling lead. Protein contained in milk can combine with lead to form insoluble matter, and calcium contained in milk can prevent the absorption of lead. Tannic acid in tea can form a soluble complex with lead, which is excreted with urine. Iodine and alginic acid in kelp can promote the discharge of lead. Sulfide in garlic and onion can dissolve the toxic effect of lead. Seabuckthorn and kiwifruit are rich in vitamin C, which can prevent the absorption of lead and reduce lead toxicity. Food contains some inorganic anions or acid radicals, such as iodine ions, phosphate ions and molybdate ions. , can combine with lead to promote its excretion from the stool. These nutrients are rich in fruits and vegetables, so people exposed to lead should eat more fruits and vegetables.
Question 4: What can lead make? 20 points China is a big country producing lead, and the specific uses of lead are mainly used in industry, classified by use:
Battery industry: Lead products (plates, electrodes and connectors) are the main structures in starting batteries and electric batteries.
Electronic products: such as household appliances (monitors) and lighters (flame nozzles)
pigment
plummet
The battery industry accounts for 90%, and non-ferrous metal mining and processing enterprises are all involved in the production and processing of lead, such as Yuguang Gold and Lead; In addition, China's recycled lead market is huge, mainly concentrated in Hebei, Inner Mongolia, Shandong and Jiangsu, and its series of products are mainly used in the battery industry.
The properties of lead make it have the function of maintaining and increasing the value of investment. Battery manufacturers of big brands, such as sails and unified camels, need long-term reserves.
Question 5: What does it mean to fish with lead? Landlord, do you want to ask whether to load lead or run lead?
Lead bag is not a fishing method, but a hook. Or lead.
If it is lead running, it only refers to fishing, which is usually used when small fish encounter difficulties or heavy winds and waves. It can reduce the chance of small fish cutting and resist wind and waves.
Question 6: What can absorb lead? Earth!
Question 7: What is the lead seal number? This is the symbol of the local electric power department.
Question 8: What are the advantages and disadvantages of lead? Lead pollution
Of all the known toxic substances, lead is the most recorded in books. According to ancient books, it is very dangerous to transport drinking water with lead pipes. There are many ways for the public to be exposed to lead. In recent years, the public is mainly concerned about the lead content in petroleum products. Lead in pigments, especially some time-honored brands, has caused many deaths, so some countries have specially formulated environmental protection standards, stipulating that the lead content in pigments should be controlled within 600PPM.
Some countries have not yet set standards, but when pigments with high lead content are sold in the market, they will put labels on them to warn users. There are also lead residues in food, or lead in the air pollutes food, or lead in canned skin pollutes canned food. Another important source of lead is lead pipes. Decades ago, lead pipes or lead-lined pipes were used to build houses, and natural refrigerators in summer were also lined with lead. Over the years, they have been banned and replaced by plastics or other materials.
The safe limit of lead content in drinking water is 100 μ g/L, and the maximum acceptable level is 50 μ g/L. Later, it was further stipulated that the maximum acceptable concentration of lead in tap water is 50μ g/L (0.05mg/L). In addition, in order to study the effect of lead on human health, scientists began to detect the lead concentration in human blood samples as an early indicator of lead poisoning. The data show that if the drinking water is close to 50 μ g/L, the lead concentration in the patient's blood sample is above 30 μ g/L ... The requirements for nursing babies should be stricter, and the average blood lead concentration should not exceed10-15 μ g/L.
Calcium and bicarbonate may be added in the water treatment process of waterworks to keep the water alkaline, thus reducing the corrosion of water to water pipelines and bringing new risks. But the corrosion problem is very complicated, and it can't be solved in this way. It should be overall purification, but it is expensive.
Many chemicals may degrade into harmless final compounds after staying in the environment for a period of time, but lead cannot be degraded again, and once discharged into the environment, it will remain available for a long time. Lead has been listed as a strong pollutant because it exists in the environment for a long time and has strong potential toxicity to many biological tissues.
At present, acute lead poisoning has been thoroughly studied, and its symptoms are: stomach pain, headache, trembling, nervousness, and even coma until death. At very low concentrations, the chronic long-term health effects of lead are as follows: affecting the brain and nervous system. Scientists have found that even if the lead concentration in blood samples of urban children is still acceptable, it still obviously affects children's intellectual development and abnormal behavior. Only by reducing the lead content in drinking water can we ensure that the total lead intake of people is reduced. The popularization and application of unleaded gasoline has made great contributions to reducing lead pollution in the environment, especially to reducing lead in atmospheric particles.
Lead and particulate matter have drifted from cities to suburbs, from one province to another, and even abroad, affecting other regions and becoming public hazards in the world. Scientists drill icicles in the area where ice accumulates year after year on the iceberg in Greenland, North America. The age of the lower layer is long, and the age of the upper layer is near, so it is easy to determine the lead content of different layers of ice. The results show that before 1750, the lead content is only 20 μ g/ton; 50 μ g/ton in 1860; 1950 rose to 120 μ g/ton; 1965 greatly increased to 2 10 μ g/ton. With the development of modern industry, global pollution is becoming more and more serious.
Lead is a chemical element, and its chemical symbol comes from Latin. The chemical symbol is Pb (Latin lead), with an atomic weight of 207.2 and an atomic number of 82. Among all stable chemical elements, lead has the highest atomic number.
Lead is a bluish silvery white heavy metal, which is toxic and is a main group metal with ductility. Melting point 327.502C, boiling point 1740C, density1.3437g/cm, hardness 1.5, soft texture and low tensile strength.
Lead is one of the earliest metals used by human beings. In 3000 BC, people had already smelted lead from ores. The lead content in the crust is 0.00 16%, and the main ore is galena. Lead has four stable isotopes in nature: lead 204, lead 206, lead 207 and lead 208, and there are more than 20 radioactive isotopes.
Metal lead contacts with oxygen, water and carbon dioxide in the air, and its surface will be rapidly oxidized to form a protective film; When heated, lead can quickly combine with oxygen, sulfur and halogen; Lead is almost the same as cold hydrochloric acid and cold sulfuric acid. & gt