Madame Curie (French physicist and chemist. Originally from Poland, 1867- 1934) When investigating pitchblende and copper ore, she found that these two minerals contain a substance that is more radioactive than uranium or thorium, and she realized that this is a new element that has not yet been recognized. She said to her husband, "If this new element can be proved in the future, I want to call it polonium to commemorate my motherland-Poland."
Although Marie Curie lived abroad and married a French scientist, pierre curie, she loved her motherland since she was a child and never forgot her motherland occupied by the Russian Empire. She wants to win pride and glory for her motherland by naming new elements! Entrust her with patriotic passion like fire. "ok!" Pierre curie said: "Poland is your motherland, and it can also be said that it is my motherland!" The intense work began, and it was eliminated day and night, and the scope of research became smaller and smaller. 1in July, 897, they separated out a new radioactive element from some minerals containing bismuth, which is similar in chemical properties to bismuth and 400 times more radioactive than pure uranium. "Ah, new elements, polonium, polonium." Madame Curie threw herself into her husband's arms and shouted excitedly, "polonium!" " Two lines of tears spilled on her husband's chest.
"Polonium, Poland! Poland, hey! " Pierre also cheered from the bottom of his heart.
The first person to enjoy oxygen was a mouse.
We know that human beings can't live without oxygen. However, who discovered oxygen? Among many works discussing the discovery of oxygen, joseph priestley's Experiments and Observations of Several Gases is the most interesting.
Joseph Pliester was born in Felthhead, near Richmond, England on March, 2003 1733. He has actually been a priest for most of his life, and chemistry is just his hobby. His experiments and observations on several gases were published in 1766. In this book, he described the various properties of oxygen in detail to the scientific community for the first time. At that time, he called oxygen a "decolourant". Priestley's test record is very interesting. One of the paragraphs reads:
"I put the mice in the' burning' air and found them very comfortable. I was driven by curiosity and tried it myself. I don't think readers will be surprised. When I do my own experiment, I suck it from a big bottle full of this gas with a glass straw. At that time, the feeling I got in my lungs was the same as that I usually inhaled ordinary air; But after inhaling this gas, after many times, my body and mind have always felt light and comfortable. Who can say that this kind of gas will not become a fashionable luxury in the future? But now only two mice and I have the right to breathe this gas! " At that time, he didn't name this gas "oxygen", just called it "desmoking". Before making oxygen, he made ammonia, sulfur dioxide, nitrogen dioxide and so on. Compared with other chemists of his time, he adopted many new experimental techniques, so he was called "the father of gas chemistry".
From 65438 to 0783, lavoisier's "oxidation theory" was widely accepted. Although priestley only believed in phlogiston, his discovery of oxygen was an important factor in the later chemical prosperity, and people all over the world still miss him.
Sharks also have nemesis?
Hemingway, who is famous for his article The Old Man and the Sea, did experiments to prevent sharks with drugs in his familiar sea area, and alternately put bait containing copper sulfate and bait without copper sulfate on the sea surface. Two days later, he was surprised to find that the shark had eaten all the bait without copper sulfate. On the contrary, the bait containing copper sulfate did not move, and Hemingway jumped up by the highlight. He finally found that copper sulfate can prevent sharks.
During World War II, the war was unprecedented cruel not only on land, but also at sea. The crew of the hit warship had to abandon the ship and flee, but faced another challenge-sharks. Therefore, the US government calls on people of insight all over the country to study anti-shark drugs. From Hemingway's story, they quickly equipped copper sulfate as a "talisman" to prevent sharks.
The history of soap
In our life, soap is indispensable for one day. Soap for washing face: bath soap; Laundry soap for washing clothes Wash your face every day. Clothes should also be washed and changed frequently. When clothes are worn for a long time, they will be sour because of dirt, oil and sweat. Oily clothes are a hotbed of bacteria. Dirty things can also corrode and destroy the fibers of the fabric, and only regular washing can prolong the life of clothes.
In ancient times, people stacked their clothes on the bluestone board by the river, beat them repeatedly with wooden sticks, and washed the dirt off their clothes with the help of clear water. Washing clothes like this is laborious and ineffective. Later, it was found that there was a trona mine, which was very greasy when dissolved in water, and it was quite effective to remove oil. The fruit of Gleditsia sinensis, soaked in water, can also be used to wash clothes. Similarly, oil stains can also be washed away.
In ancient Egypt, it was found that some winter and winter mixed with plant ash and some sheep fat could decontaminate. This is probably the earliest soap. In ancient France (then called Gaul), people made a coarse soap with plant ash water and goat oil, which is a bit like the shampoo in our barbershop today. Later, people mixed lard with trona, kneaded and squeezed it repeatedly, and got the "pig pancreatic soap" similar to today's soap.
My grandparents used this kind of pig pancreatic soap! This is why soap is called "pancreas" in some places.
The soap we use now is boiled from the cauldron in the factory. Put butter, lard or coconut oil in the cauldron of soap factory, then add caustic soda (sodium hydroxide or sodium carbonate) and boil it with fire. Oil and sodium hydroxide chemically change to produce soap and glycerin. Because soap is insoluble in concentrated salt water, while glycerol is very soluble in salt water, soap and glycerol can be separated by adding salt. So after cooking for a while, pour in some fine salt powder, and a thick layer of sticky paste emerges from the cauldron. Scrape it into a soap model box with a scraper and cool it to form a soap bar. Medicinal soap is similar to ordinary soap, except that some disinfectant is added. Soap is generally made of coconut oil and olive oil, and spices and colorants are added, so there are soaps that emit various flavors and colors. Glycerol is an important by-product of soap industry. Glycerol is of great use in national defense, medicine, food, textile and so on. Soap was also called "devil's cream" before liberation because many of its ingredients came from Japan.
Mysterious warship fire case
Once upon a time, a huge fleet of ancient Roman Empire sailed triumphantly. The fleet approached the Red Sea, and suddenly, the biggest supply ship came out with thick smoke, covering the sky. The expeditionary warship had to close its sails and turn back to Hong Kong.
The commander-in-chief of the expeditionary force was not reconciled and tried his best to find out the cause of the fire on the supply ship. However, after searching, the cook has been found from the commander, the horse has been abandoned, and no one has set fire to it.
This historical mystery is the result of later scientists' research and found the cause of the fire. It turned out that the grass piled at the bottom of the supply ship spontaneously ignited. This phenomenon is called spontaneous combustion.
How can grass spontaneously ignite?
The grass supplied to the bottom of the ship is squeezed tightly, and some of it begins to slowly: oxidation, which is actually a slow combustion, gives off heat and cannot be dissipated. The more heat accumulated, the higher the temperature, and finally reached the ignition point of grass, so it spontaneously caught fire.
Spontaneous combustion is not uncommon in our life. Haystacks in rural areas and coal piles in factories sometimes emit steam inexplicably, and even smoke and catch fire. Some abandoned coal mines often spontaneously combust continuously. Knowing the scientific causes of spontaneous combustion, we can find ways to prevent it.
When stacking coal and firewood, the stack should not be too large or too high to prevent heat accumulation.
In the center of the coal pile, several iron baskets are buried, and iron pipes extend from the baskets to the top of the coal pile, so that the accumulated heat in them can be quickly dissipated.
Keeping good ventilation can remove the tropical zone produced by slow oxidation and reduce the temperature. The temperature condition of combustion and spontaneous combustion are eliminated. Experienced warehouse staff often rummage through boxes to prevent combustible materials from burning in vain.
Of course, it doesn't mean that you can prevent it if you want to. Please pay more attention to the "Flame Mountain"-the burning underground coal mine in Xinjiang!
The tragic course of discovering fluorine
In the history of chemical elements, the research topic with the largest number of participants, the greatest danger and the most difficult work is the discovery of fluorine. After the discovery of hydrofluoric acid by German chemist Magraff (A.S. 1782) in 1768, until 1886, many chemists such as French chemist Mu Wasang (H. 1852-65438+) damaged their health and even sacrificed their lives.
1768, Magraff studied fluorite and found that it is different from gypsum and barite, so it is not sulfate. 177 1 year, chemist Scheler used retort to heat the mixture of fluorite and sulfuric acid, and found corrosive agent on the inner wall of glass bottle. 18 10 French physicist and chemist Ampere pointed out that hydrofluoric acid may contain an element similar to chlorine. Chemist David's research also reached the same view. 18 13 David made elemental fluorine by electrolytic fluorination, and used gold and platinum as containers, all of which were corroded. Later, fluorite was used as a container. Although the corrosion problem was solved, fluorine could not be obtained, and he stopped the experiment because of illness. Then George Knox (G.) and Thomas Knox (R.T.) first treated the dried mercury fluoride with dry chlorine, and then put a piece of gold foil on the top of the glass receiving bottle. The experiment proved that gold turned into gold fluoride, indicating that fluorine was produced in the reaction, but no fluorine was obtained. In the experiment, both brothers were seriously poisoned. After the Knox brothers, Runje (P.) studied fluorine for a long time, and finally died of overdose. French chemist Nicholas suffered the same fate. Freimut (Freimut, e1814-1894) is a chemist who studies fluorine. He used to electrolyze anhydrous calcium fluoride, potassium fluoride and silver fluoride. Although metals can precipitate at the cathode and produce a small amount of gas at the anode, they are never collected.
At the same time, British chemist Al Gore (D.G. 1826- 1908) also decomposed hydrogen fluoride by electrolysis, but an explosion occurred during the experiment, and a small amount of fluorine obviously reacted with hydrogen. He used carbon, gold, palladium and platinum as electrodes. In the process of electrolysis, carbon is crushed and gold, palladium and platinum are corroded. Although the efforts of so many chemists failed to produce elemental fluorine, their experience and lessons were extremely valuable, which created favorable conditions for the preparation of fluorine later.
Movasan was born in a family of railway clerks in Paris. Because of his poor family, he became a pharmacist's assistant before he graduated from middle school. He has a strong thirst for knowledge and often goes to lectures by some famous scientists. 1872 studied chemistry in the laboratory of Freimut, curator of French Museum of Natural History and professor of Polytechnic. 1874 worked in the laboratory of the Institute of Pharmacy in Paris, and 1877 obtained the bachelor of science degree. 1879 passed the pharmacist examination and served as the laboratory director of higher pharmaceutical college. From 65438 to 0886, he became a professor of toxicology in the College of Pharmacy. 189 1 was elected as an academician of the French academy of sciences. 1907 died in Paris on February 20th. He has made many inventions in chemistry, and now he mainly introduces his research on fluorine.
1872 Movasan became a student of Professor Freimut and began to work in a real chemistry laboratory.
Professor Freimut was a chemist who studied fluoride at that time. Under his instruction, Movasan not only learned the general change law of chemical substances, but also learned the chemical knowledge and research process about fluorine. He knew that as early as 1960s, Ampere and David had proved that hydrochloric acid and hydrogen acid were two different compounds. The latter compound contains fluorine. Because this element has a particularly strong reaction ability, it can even react with glass, so that people can't separate free fluorine. Fremut did many experiments over and over again, but didn't find anything that didn't work with fluorine. Although he knows that it is difficult for many chemists to make elemental fluorine, he is very interested in the study of fluorine. Not only was he not intimidated by the difficulty, but he was determined to overcome it. Due to the change of work, this research was not carried out in time, so I didn't concentrate on it until 10 years later.
Movasan first spent several weeks consulting the scientific literature and studied almost all the works on fluorine and its compounds. He believes that none of the known methods can separate fluorine alone, and only the method envisaged by David has not been tested. David thinks that there is a strong affinity between phosphorus and hydrogen. If phosphorus fluoride can be prepared and then reacted with oxygen, phosphorus oxide and fluorine may be generated. Because there was no method to prepare phosphorus fluoride at that time, the envisaged experiment was not realized. So Movasan reacted with lead fluoride and copper phosphide to get gaseous phosphorus trifluoride, and then the mixture of phosphorus trifluoride and oxygen passed through electric spark. Although an explosion reaction was also made, phosphorus oxyfluoride was obtained instead of elemental fluorine.
Movasan carried out a series of experiments, all of which failed to achieve the goal. After a long period of exploration, he finally came to the conclusion that all his experiments were carried out at high temperature, which was the crux of the failure of the experiment. Because fluorine is very active, its activity increases greatly with the increase of temperature. Even if it can be separated in a free state during the reaction, it will immediately combine with any substance. Obviously, the reaction should be carried out at room temperature. Of course, it would be better if it could be carried out under cooling conditions. It seems that electrolysis is the only feasible method. He thought, what if some liquid fluoride is used for electrolysis, such as arsenic fluoride? This idea is obviously promising. Movado began to prepare highly toxic arsenic fluoride, and then it encountered new difficulties. It was found that arsenic fluoride was not conductive. In this case, he had to add a small amount of potassium fluoride to arsenic fluoride. This mixture has good conductivity, but a few minutes after the start of the reaction, the surface of the cathode is covered with a layer of arsenic precipitated by electrolysis, so the current is interrupted. Movasan was very tired and struggling. He turned off the power of Unicom electrolyzer and immediately fell on the sofa. He suffers from severe heart disease, difficulty breathing, yellow face and dark circles around his eyes. Movasan thought arsenic was at work, so I'm afraid he had to give up the plan. This phenomenon is not the first time, because the poisoning experiment was interrupted four times. Movasan's beloved wife, Leonie, saw him doing more work for herself without restraint, and she often risked poisoning and was extremely worried about his health.
However, Movasan continued to experiment and designed to electrolyze hydrogen fluoride at low temperature. Since dry hydrogen fluoride is not conductive, a small amount of potassium fluoride is added to it. He put the mixture into a U-shaped platinum tube and then electrified it. Hydrogen bubbles appeared quickly on the cathode, but there was no gas decomposition on the anode. Electrolysis lasted for nearly an hour, and all the hydrogen was decomposed, not even a trace of fluorine. Movasan removed the instrument and thought distressfully that perhaps fluorine could not exist in a free state at all. When he unplugged the plug at the anode end of the U-shaped tube, he was surprised to find that the plug was covered with a layer of white powder. Yes, the atomic plug has been corroded! After all, fluorine decomposes, but it reacts with glass. This discovery greatly encouraged Movasan. He thought that if all the glass parts on the device were replaced with materials that could not react with fluorine, monomer fluorine could be prepared. Fluorite does not react with fluorine, so try it, so make fluorite into an experimental vessel. Movasan immersed a U-shaped platinum tube filled with a mixture of liquid hydrogen and potassium fluoride in a refrigerant, used platinum-iridium alloy as an electrode, covered the nozzle with a nut made of fluorite, used methane chloride as a refrigerant outside the tube, and controlled the temperature at -23℃ for electrolysis. Finally, elemental fluorine was prepared for the first time in 1886. The famous chemist examined Movasan's work and thought it was indisputable. In recognition of his outstanding contribution to fluorine production, the French Academy of Sciences awarded him the La Cazier Prize of 1 10,000 francs. Twenty years later, he won the 1906 Nobel Prize in chemistry for his outstanding achievements in the preparation of fluorine and its compounds.
The interesting thing about lime is that
Why does cold water heat or even boil when it meets cold lime? ※
At first glance, this is really strange. Where does the heat come from? It turns out that as soon as quicklime (calcium oxide) meets water, it immediately reacts to generate so-called hydrated lime (calcium hydroxide). This chemical reaction is a kind of exothermic effect, just like the chemical reaction after coal is ignited in the air, it will also release heat. The heat released by the reaction of quicklime with water is quite large, such as the heat released by the reaction of one kilogram of quicklime with water. If there is no loss, 3.5 kilograms of water can be boiled. Isn't it amazing?
Why is it so hard to dry after lime is painted on the wall? ※?
We know that soil will dry quickly when painted on the wall, but lime often doesn't dry for a few days after painted on the wall. Why? It turns out that hydrated lime (calcium hydroxide) generated by the reaction of quicklime with water reacts with carbon dioxide in the air to become calcium carbonate and water. The content of carbon dioxide in the air is very small, because this chemical action progresses very slowly. So after a long time, the wall is not easy to dry because water is generated by the reaction.
Why is the lime wall getting harder and whiter? ※?
We already know that hydrated lime (calcium hydroxide) reacts with carbon dioxide to produce calcium carbonate and water. Calcium carbonate is very hard and white. Because calcium hydroxide is soft, the reaction slowly turns into calcium carbonate, so the lime wall becomes harder and whiter.
Two atomic bombs in 1945
1945 Summer, World War II is coming to an end, Hitler's Nazi rule has been overthrown, and the defeat of Japanese fascist bandits in China and Asia is doomed. 16 In July, the United States successfully exploded the world's first atomic bomb at the Alamogordo desert test site in New Mexico, and quickly decided to use it to bomb Japanese cities. In order to ensure the smooth progress of the raid, the United States made a series of careful preparations in advance, especially when determining the date of the raid, putting meteorological conditions in a prominent position. In the combat order approved by US President Truman, there is a passage: "After August 5, as long as the weather permits, the 509th Brigade can use special bombs (referring to the atomic bombs that were not made public at that time) to visually bomb and raid one of the targets such as Hiroshima, Kokura and Nagasaki." "Weather permitting" here refers to the flight meteorological conditions and the vertical visibility conditions above the target. Hiroshima, Kokura, Nagasaki and other cities are chosen because these cities are important places for military facilities or arms industry, and it is easy to achieve deterrent effect after bombing.
Hiroshima has a loading and unloading military port, a developed arms industry, and the second Japanese army and a military command are stationed. At that time, Hiroshima had not rained for three weeks, the weather was very dry and buildings were easy to burn, so it was the first choice for US bombing. Kokura is located at the northern end of Kyushu Island in Japan. It has industries such as steel and arms, and is also a railway hub. It has been identified as the second goal. Nagano, located in the west of Kyushu Island, is a port and industrial city. Because it is located in a low-lying valley, it is selected as a reserve target only after it cannot be airdropped due to bad weather conditions or other reasons. When dropping an atomic bomb, you should avoid wind, rain and thunder, and absolutely ensure flight safety. It can be seen that meteorological support is very important and the first condition to ensure the success of throwing. Therefore, the US military requires the meteorological department to know the weather information of Japan in time and make the weather forecast of the target city at least 24 hours in advance, so as to have enough preparation time before bombing.
On August 2nd, the B-Z9 bomber of the 509th Brigade carried the assembled atomic bomb on Tianning Island, USA, waiting for the right weather. On the 2nd, 3rd and 4th, the weather was always bad, cloudy and sometimes rainy, so the plane could not take off. The US Supreme Command is very annoyed and anxious about this, and sends weather reconnaissance planes to take off every day for observation. On August 5, the US military meteorological department analyzed a large number of meteorological data and predicted that Hiroshima would be sunny after the rain on the 6 th. Both the aircrew and the ground crew made preparations in advance. Sure enough, in the early morning of the 6th, the weather reconnaissance plane reported that Hiroshima was sunny, with few clouds and good visibility. So, near 3 am, the plane carrying the atomic bomb and other planes took off from the base in the night. Under sunny and cloudy weather conditions, American planes dropped the first atomic bomb on Hiroshima. Hiroshima suffered a devastating bombing, causing heavy casualties. According to the data of the United States and Japan, the first atomic bomb killed 7 1379 people in Hiroshima, injured 68,023 people, and all industrial machines were destroyed. The success of air strikes is due to the outstanding role of meteorology. According to the United States, due to the good visibility in the atmosphere, the throwing deviation of a five-ton atomic bomb is only 240 meters.
When the first atomic bomb raid was successful, because Japan did not surrender immediately, the United States planned to drop a second atomic bomb, targeting Kokura. The raid date was originally scheduled for August 1 1, but according to the weather forecast of the US military meteorological department, it will be sunny only on the 9th, followed by five days of bad weather, so it is impossible to drop an atomic bomb. On August 8, the former Soviet Union declared war on Japan. Considering various factors, the US Supreme Command decided to advance the bombing date to 9th. At about 4 am on the 9th, two weather reconnaissance planes and two bombers took off from the US Air Force Base and flew to Kokura. After arriving over the small warehouse, the weather was not as sunny as predicted by the military meteorological department. The whole sky is overcast and foggy, and the pilot can't see the target with the naked eye. According to General Ashworth, who was in charge of bombing at that time, the bomber lowered its flying height five times in a row and tried to throw it, but the visibility was too poor to find the target, so the plane had to fly to Nagasaki as planned. Unfavorable meteorological conditions prevented the small warehouse from a disaster.
When the bomb-carrying plane arrived over Nagasaki, it was found that Nagasaki was also covered with thick clouds, and the meteorological conditions were much worse than predicted, so it was impossible to drop bombs visually. However, at this time, the fuel of the aircraft is running out, and the fuel tank and fuel pump are not smooth in time, so it is impossible for the aircraft to take the bomb back to China. The pilot received the order to drop the bomb, so he temporarily decided to use radar to identify and find the target. After hovering for about 10 minutes, the bomber is ready to drop the bomb. At this time, a gap suddenly appeared in the clouds over Nagasaki, and a runway in the valley could hardly be seen through the gap. So at 10: 58 local time, the second atomic bomb was dropped on Nagasaki. Because Nagasaki is located in the valley, the meteorological conditions were not good and the visibility was poor, which made the bombing deviate from the target by about 2000 meters. In addition, there was no wind that day, so the casualties and material losses caused were smaller than those in Hiroshima. According to the information provided by Japan, the atomic bomb killed 35,000 people, injured 60,000 people, disappeared 5,000 people and left 68 people. 3% of the factories were destroyed.
Inspired by spiders
More than 300 years ago, a young British scientist became interested in the spider "General Bagua Fei". He often observes spiders from morning till night. He saw the spider busy weaving a web. The filament just pulled out of the spider's sac is mucus. Blown by the wind, it instantly becomes tough and strong spider silk.
The young scientist thinks it would be great if he could invent a robot spider, "eat" chemicals and draw crystal silk to spin and weave! He plunged into the chemistry laboratory, fiddling with bottles and jars and doing experiments with various chemicals. He treated cotton with nitric acid to get nitrocellulose, dissolved it in alcohol to make it a viscous liquid, passed through a glass tube, let the alcohol evaporate in the air, and then it became a filament. This is the first man-made fiber in the world. But this kind of fiber is easy to burn, poor in quality and high in cost, so it can't be used for spinning and weaving.
Later, scientists imitated silkworms, dissolved lignocellulose from cheap and easily available wood in caustic soda and carbon disulfide to make mucus, and then spun silk under the water surface, pulling out countless knots. This is the famous "rayon" (viscose fiber), whose long fibers can be woven into rayon printed silk and artificial stockings. Short fibers make "artificial cotton" cloth and "artificial wool". They are comfortable to wear, similar to cotton and linen fabrics: breathable, easy to absorb water, can be dyed into beautiful colors, cheap and popular. In this way, man-made fibers have replaced one-tenth of cotton, hemp, silk and wool only 30 years after their appearance.
However, people are not satisfied. Rayon and rayon are not strong when wet, and are easy to deform and shrink after washing. In addition, although man-made fibers have expanded the sources of raw materials and used wood, short cotton fibers and grasses that cannot be directly spun, their resources are limited after all. As a result, people's eyes jumped from natural fibers to minerals. Can stone, coal and oil become fibers?
Fifty years ago, polyvinyl chloride fiber (PVC) made of coal, salt, water and air appeared in Germany. Its chemical composition is the same as that of the most common plastic. This is the earliest synthetic fiber. Cotton sweaters and sweaters, as well as sweaters made of PVC, are warm and easy to rub, and they are static. Wearing them is good for treating arthritis.
Nylon (nylon), born a few years later than chlorine fiber, is thinner than spider silk, but it is strong, crystal clear and transparent, and suddenly people are fascinated by its great charm. Nylon socks are strong and wear-resistant, and a pair of ordinary cotton socks can be worn. Polyester, once very popular, is a kind of synthetic fiber with the largest output, which is crisp and wrinkle-free. Acrylic fiber, commonly known as "synthetic wool", is fluffy and sun-resistant. We are all familiar with wool, blankets and knitted underwear made of it. Cheap and durable vinylon, woven into vinylon, can be used as bed sheets or underwear, and its water absorption and breathability are similar to those of cotton fabric. Vinylon batting is similar to cotton and is called "synthetic cotton". Besides polyester, nylon, acrylic fiber and vinylon, polypropylene polymerized from propylene has also become a new synthetic fiber.
Polypropylene is a kind of synthetic fiber with the lightest specific gravity. Blankets on airplanes and clothes for astronauts are made of it, which can reduce the burden of launching. Nowadays, the annual output of chemical fiber is equivalent to that of natural fiber, but its role in national economy and national defense far exceeds that of natural fiber. However, today's large-scale "machine silkworm" runs around the clock, thanks to the enlightenment of silkworm spinning and spider weaving!
The strange thing about bordeaux grapes is that
Bordeaux in France is rich in grapes, so "Bordeaux wine" is famous all over the world. However, in 1878, a plant virus named "mold leaf disease" swept through Bordeaux, so the vineyard quickly became fragmented and faced with crisis. Gardeners are in a hurry, but there is nothing they can do. Milad, a careful Frenchman, found a strange thing: the vines on the roadside were lush and did not suffer from mildew. It is found that these vines are sprinkled with some blue and white things from leaves to stems. After inquiring, it was discovered that the "poison" sprinkled by the shopkeeper to prevent passers-by from gluttony was made of lime and blue alum. Practice has proved that it is a good pesticide for controlling moldy leaf diseases. Since then, Bordeaux has become a "vineyard world". At the same time, this pesticide is named after "Bordeaux mixture" and is widely circulated all over the world. The chemical principle of this pesticide is that lime reacts with copper sulfate to produce basic copper sulfate, and the product has strong bactericidal ability. ca(OH)2+2 cuso 4 = caso 4+Cu(OH)2so 4
14 Jin of meat "changed" 1 gram of radium.
This is an old shack that nobody uses. The glass ceiling is broken and there is air leakage. There is no floor inside, only a layer of asphalt covers the dirt floor. There is not even a decent stool, only a few rotten cupboard tables, a blackboard and an old iron stove with rusty pipes on it.
From 65438 to 0889, Madame Curie and her husband began to refine radium in this humble room. Madame Curie wears overalls covered with dust and stains every day, turns over ore, stirs the smelting pot, pours the solution and works nonstop. In the small laboratory, iron filings were flying and steam was smoking, while Madame Curie was suffering from tuberculosis at that time, but she still worked stubbornly despite these. I often bring my meals to the lab to eat, let alone have a rest. Sometimes I use a heavy iron bar to stir a lot of boiling things all day. At night, I was exhausted and couldn't move.
In this way, after 45 months' efforts, the Curies finally extracted a trace of 1g pure radium from 400 tons of uranium asphalt residue, 1000 tons of chemicals and 800 tons of water. However, Madame Curie lost weight 14 Jin!