Ten chemical reactions that changed the world

10. Ammonia synthesis

Nitrogen is one of the most important elements in life, perhaps second only to carbon. It is a key component of DNA, RNA, protein, and chitin (a biopolymer similar to cellulose found in fungi, insects, lobster, shrimp, and certain fish). Nitrogen is also one of the most abundant elements on earth, accounting for about 78% of the earth’s atmosphere. However, nitrogen in the atmosphere exists in the form of N2, which is highly inactive and useless for most life forms. Therefore, nitrogen must be fixed by converting it into a more reactive form (such as ammonia, nitrate and nitrite). In nature, this is usually done by specialized bacteria. These bacteria form a symbiotic relationship with many plants living in root nodules (which means that both organisms benefit). However, not all plants form this relationship. Especially in the case of commercial farming, crops such as corn do not fix nitrogen, but absorb nitrogen from the soil. If crops that cannot fix nitrogen are grown for several seasons, it is necessary to add fertilizer. However, few natural substances have enough nitrogen as fertilizer. Therefore, in order to meet the increasing demand for food, it is necessary to find a better method of producing nitrogen fertilizer. The Haber-Bosch process is the first step. The process was developed by Fritz Haber and Carl Bosch in 1918 and used high temperature and high pressure and iron catalysts to produce large amounts of ammonia from gaseous hydrogen and nitrogen. As the production price of ammonia is relatively cheap, it has become a viable substitute for natural fertilizers. Today, in terms of tonnage, ammonia is the second most produced chemical after sulfuric acid.

9. Polyethylene polymerization

Plastics have completely changed the world. Because they are easy to mold, heat and chemical resistant, and cheap to manufacture, plastics have become a commonly used material in daily life, especially polyethylene. It comes in many forms, such as high-density polyethylene and low-density polyethylene, and can be used in plastic bags, baby bottles and even bulletproof vests. In 1933, two scientists working at the Imperial Chemical Industry Research Laboratory accidentally discovered polyethylene while trying to react ethylene with benzaldehyde. In contrast, waxy materials have been discovered, which are polymers of ethylene. A polymer is a substance composed of many repeating units. Other polymers include cellulose and DNA. By 1937, this material had been developed into a thin film and was used by the British as an insulating material for wires and radar components in World War II. Since it makes electrical components light enough to be placed on an airplane, its structure and manufacturing are highly protected secrets. Today, polyethylene is the most produced plastic in the world, producing 81.8 million tons in 2015, and it is estimated that nearly 100 million tons will be produced in 2018.

8. Hydrogen combustion

In the late 1700s, chemistry was an underdeveloped science. Most of the chemistry originates from the elements of air, water, earth and fire in Greece, and some ingredients are added as needed to explain the observation results. One of the most significant additives is inflammatory factors. The concept was developed by Georg Stahl and pointed out that all flammable substances contain a fire element called fire element. When burned, this phlogiston will be lost to the air. Th Phenibut on sale is seems to explain why the burnt charcoal is lighter than the original charcoal. However, this theory cannot explain why certain substances (such as phosphorus and sulfur) increase mass during combustion. Enter the French scientist Antoine Lavoisier, who is very skeptical of the flare theory. In perhaps his most famous experiment, he burned so-called flammable air (hydrogen) with ordinary air. The product is water. Lavoisier believes that water must be a mixture of a substance in the air (he called it oxygen) and flammable air. He further supports his hypothesis by splitting water into oxygen and hydrogen. In 1789, Lavoisier’s new chemical system was completely published in his textbook “Traite elementaire de Chimie” (“Chemical Elements”), which abandoned the Greek system and laid the foundation for modern chemistry.

7. Reduction and oxidation of zinc and silver

In 1745, Alessandro Volta (Alessandro Volta) was born in Como, Italy. Little is known. As we all know, it can conduct electricity, and there are two forms (later called positive and negative). Shortly after Walta was born, Benjamin Franklin proved that lightning is actually electricity. Although Volta did not have a college degree, he was widely known as a scientist in his time. In 1775, he developed a permanent electrophoresis apparatus, which improved the previous electrophoresis apparatus. However, another invention is his most important. In 1780, the scientist Luigi Galvani declared that the muscles of animals produce electricity when they contract. He called this “animal use of electricity” and thought it was different from conventional electricity. Volta disagreed with this, and pointed out that Galvani’s frog legs had been connected to two different metals during the experiment. Volta went on to prove that by stacking alternating silver and zinc metal discs on top of each other and using a cloth soaked in salt water between each disc, he could generate a steady current without animals. However, people immediately realized that Volta’s invention was much more useful than resolving the dispute with Galvani. All electricity in the past could only be generated suddenly. By generating a stable current, Volta’s invention can be more rigorously studied, thereby laying the foundation for Faraday’s revolutionary work in electromagnetics.

Synthesis of 6 Urea

Lifeism is a theory that believes that living systems are governed by completely different principles from non-living systems. In addition, it is believed that the components that make up a living system cannot be composed of non-living components. This belief was widely used in the 19th century and was used to explain why many biological systems seem puzzling compared to non-biological systems. However, German scientist Friedrich Wohler changed this. Wohler was famous for the separation of pure aluminum in 1825, and he was trying to synthesize ammonium cyanate in 1828. However, when he reacted silver cyanide with ammonium chloride in an attempt to produce ammonium cyanate, he instead produced white crystals. He later determined that the substance was urea. Urea was separated in 1773 by the French chemist Hilaire-Marin Rouelle. This means that Waller has just synthesized an organic compound, which refutes one of the basic principles of lifeism. Waller’s work will continue to lay the foundation for the field of organic ch China Phenibut emistry.


So far, polymerase chain reaction (PCR) is the most complex reaction on this list, but it may be the most useful and exciting reaction. PCR was invented by Kary Mullis in 1983, and his work eventually won the Nobel Prize. This process works by heating the DNA to separate it into two single strands. (DNA is double-stranded.) Then primers can be attached to each DNA strand. An enzyme called DNA polymerase attaches to the primer site and replicates the rest of the DNA chain. This process can be repeated many times, and in theory each iteration will double the exact DNA copy number. The ability to replicate DNA has opened the door to many areas. Even if only a small amount of genetic material is left at the crime scene, forensics can use genetic technology. In medicine, it helps to determine the cause of infection. In research, it is an essential technology used in human genome sequencing. In addition, it has now become a universal technology in biology and biochemistry laboratories worldwide.

4. Fat moisturizing

Do you have a can of Crisco in your storage room? Would you be surprised if I told you that Crisco is the result of the world’s most revolutionary food technology advancement? It all starts with the difference between animal fat and vegetable fat. Fat in animals tends to be saturated, which means that all the carbon in the fat is combined with the maximum number of atoms. Fats in plants are often unsaturated, which means that some of the carbon in these fats is not combined with the maximum number of atoms. In 1902, Wilhelm Normann (Wilhelm Normann) developed a process that can add hydrogen to unsaturated fat, thereby converting it into saturated fat or at least a higher degree of saturated fat. In 1909, Procter & Gamble obtained a Norman patent. Two years later, they released Crisco, a shortening made mainly from hydrogenated cottonseed oil, which is cheaper than standard lard. But this is only the beginning. By 1979, approximately 60% of all fats consumed in the United States had been hydrogenated. But hydrogenation has a dark side. Almost all natural unsaturated fatty acids exist in the cis configuration, which causes the fat molecules to have bends or kinks in them, and they cannot fuse with each other. This is why most unsaturated fats are liquid. However, during the hydrogenation process, some unsaturated fatty acids assume a trans configuration. Since the 1990s, studies have shown that large intakes of trans fats can have an adverse effect on health. Soon thereafter, the FDA began to monitor the content of trans fats in food, and some areas even banned the use of these substances. This leads to a final reduction in hydrogenated fats.

3. Destruction of ozone

At least since the 1870s, mechanical refrigeration technology has been widely used. However, there was a huge problem that limited the technology at the time. Most refrigerants (substances used to transfer heat from the inside of the refrigerator to the outside) are highly toxic or flammable. Unfortunately, due to refrigerant leakage, deaths are relatively common. In order to solve this problem, Frigidaire, Dupont and General Motors worked together to find a safer refrigerant. The result is Freon, a mixture of chemicals called chlorofluorocarbons (CFC). Freon is so safe that its inventor directly inhaled it and then inhaled it into the candle in Phenibut powder wholesale front of the American Chemical Society. However, CFCs had an unknown problem at the time. With so many refrigerators using CFCs, the chemicals quickly reached important levels in the atmosphere. When exposed to ultraviolet rays in the upper atmosphere, CFCs often release chlorine atoms. Chlorine has high reactivity and can catalyze the decomposition of ozone (O3) into molecular oxygen (O2). As a catalyst only accelerates the reaction rate and is not consumed during the reaction, one molecule of a CFC may cause the destruction of thousands or even millions of ozone molecules, leading to large-scale depletion of the ozone layer. Now, CFC has been strictly regulated by the Montreal Protocol and is no longer used as a refrigerant. They have been replaced by a similar class of compounds called hydrofluorocarbons (HFC). Although HFCs also have disadvantages (they are very strong greenhouse gases), there is no newly developed non-toxic and non-flammable refrigerant.

2. Carbon dioxide water

Carbon dioxide may be known for its role as a greenhouse gas. As the level of carbon dioxide in the atmosphere rises, so does the global average temperature. However, there is a second disadvantage of carbon dioxide, which occurs every day when drinking soda. Carbon dioxide reacts reversibly with water to form carbonic acid. Then, some carbonic acid decomposes into bicarbonate ions, and then into bicarbonate ions, while releasing H + (release of H + is the defining characteristic of the acid called Bronsted-Loric acid). This acid is part of the keen sense of fresh soda. However, carbon dioxide in the atmosphere can react in the same way as water in the ocean. In fact, the ocean absorbs about a quarter of the carbon dioxide released each year. As a result, since the beginning of the industrial revolution, the pH of surface seawater has dropped by about 0.1 pH units, which has increased the acidity by nearly 30%. Although the increase in acidity benefits certain organisms such as algae and seaweed, it is harmful to many organisms such as oysters, clams, shellfish and corals. A United Nations report estimates that by 2100, the cost of ocean acidification may be as high as $1 trillion.

1. Saponification

As we all know, oil and water do not mix. The reason is related to the concept called polarity. In short, water molecules are polar, oil molecules are not. Since water molecules are polar, being adjacent to each other is more advantageous than being adjacent to non-polar oil molecules. However, as any chef knows, this can cause problems when cleaning dishes. The grease will not mix with water and stay on the plate. The answer is soap. Soap molecules have polar and non-polar parts. The polar part is mixed with water and the non-polar part is mixed with oil, which makes the oil form small droplets in the water that are easier to remove. The reaction used to produce soap is the saponification reaction. Originally, soap was made by heating salt, ashes and animal fat together in water. The first known soap was made using this method in Babylon in 2800 BC. Today, soap is made by reacting sodium hydroxide or potassium hydroxide with fatty acids (derived from fat molecules). However, for purposes other than personal hygiene, soap has been replaced by detergent. These cleaners are similar to soaps, but are usually derived from petrochemical products and have several advantages over soaps. They tend to last longer without breaking down. They also tend to be more soluble in cold or hard water (water with a relatively high calcium content), which means that we are unlikely to see this nasty soap scum.