3-Thiopheneethanoic acid

Arsenic, or arsenic trioxide, is highly toxic and rarely beneficial. If its use is emphasized, there are the following aspects in ancient times.
One is in the field of medicine. In ancient times, although doctors were well aware of the toxicity of arsenic, they would use it cautiously in the treatment of certain special diseases. For skin diseases such as scabies, syphilis, and acne, arsenic has the effect of eroding sores and removing rot. After being specially processed, it can be used in very small amounts, or it can help remove bad meat and carrion, and promote the growth of new muscles. "Compendium of Materia Medica" contains: "Pi, the sex is as fierce as a pi, hence the name. The living kill, and the refined save people." It is emphasized that its rational application through refining can cure diseases. However, this usage is extremely risky, and a little carelessness can cause poisoning and even death.
Second, in agriculture. Arsenic has a certain toxic effect on pests. The ancients applied it to farmland in extremely dilute concentrations to prevent pests from eating crops, such as locusts. However, due to the lack of accurate measurement and protective measures, it often causes soil pollution, and the residual toxicity of crops is also harmful to human and animal health.
Third, in industrial use. Although the industry in ancient times was not as developed as it is today, in the process of metal smelting, arsenic can be used as an additive to improve some properties of metals. For example, when refining a specific type of copper alloy, a small amount of arsenic can make the alloy tighter, harder, and improve the quality and durability of metal products.
It should be emphasized that arsenic is extremely toxic, and a small amount can cause death. Even in ancient times, it was mostly helpless and risky. Today, there are safer and more effective alternatives, and arsenic is basically no longer used for these purposes. It is only used under strict control and protection in very special scientific research scenarios.

Arsenic, or arsenic trioxide, is a highly toxic substance. Its physical properties are as follows:
Arsenic is a white crystalline powder under normal conditions, with a fine texture, resembling frost and snow, hence the name. Its appearance is pure and white, without special color impurities, and occasionally reflected in light. It looks ordinary, but it hides a deadly danger.
Arsenic has a relatively high density and feels heavy. In an environment at room temperature and pressure, its chemical properties are stable and it is not easy to react on its own. However, when encountering specific chemical reagents, it can show a lively side.
Arsenic has a melting point of 320.2 ° C and a boiling point of 465 ° C. When heated, arsenic will gradually change from a solid state to a liquid state, and then gasify into a colorless gas. However, it is necessary to pay close attention to the fact that this gasification process will release highly toxic vapors, which can be life-threatening if inhaled accidentally.
Arsenic is slightly soluble in water. When dissolved, it disperses slowly in the water, and the dissolution speed is not fast. Although the formed solution is colorless and transparent, it is highly toxic. In addition, arsenic can also dissolve in acid and alkali solutions, causing complex chemical reactions to generate other compounds.
Because of its highly toxic properties, it was often used as a means of murder by people with bad intentions in ancient times, and it frequently appeared in many public cases, which made people feel discolored. Even a small amount of arsenic entering the human body can cause serious poisoning symptoms and endanger life and safety. When using, storing, and touching related items, it is necessary to be extremely cautious to prevent accidental contamination and lead to unimaginable consequences.

Arsenic, that is, arsenic trioxide, has unique chemical properties. Arsenic is usually white powder or crystal, which is extremely toxic.
In terms of its chemical activity, arsenic has certain oxidizing properties. When encountering strong reducing agents, the arsenic element in it can be reduced. For example, with active metals, such as zinc, under certain conditions, arsenic gets electrons and its valence decreases to form low-priced compounds containing arsenic.
Arsenic can react with acids. When encountering strong acids such as hydrochloric acid and sulfuric acid, corresponding arsenates can be formed. During this process, the structure of arsenic is destroyed, and arsenic element exists in the product in a new compound state.
In alkaline solution, arsenic can also react. It can react with bases to form arsenite salts. This reaction exhibits the acidic oxide properties of arsenic, which can be neutralized with bases to produce salts and water.
Furthermore, arsenic can participate in many complex chemical reactions when heated or in the presence of specific catalysts. Or decompose, or combine with other substances to form new compounds. However, due to its highly toxic nature, extreme caution must be taken in experimental investigation and industrial application, and strict operating procedures must be followed to prevent accidental poisoning accidents.
Arsenic has complex and unique chemical properties and is of great significance in the field of chemical research. However, due to its highly toxic nature, applications and research require careful handling.

The synthesis method of fugu acid has been around for a long time. One method is to use glutaraldehyde as a raw material and obtain it by oxidation. Glutaraldehyde, which has an active aldehyde group, can be oxidized to a carboxyl group by suitable oxidants, such as manganese dioxide and potassium dichromate, under appropriate reaction conditions, so as to form glutaric acid. This reaction process requires careful control of the reaction temperature, time and amount of oxidant to prevent excessive oxidation and formation of impurities.
There are also those who use cyclopentanone as the starting material. Cyclopentanone is first rearranged by Baeyer-Villiger oxidation. Commonly used peroxy acids, such as m-chloroperoxybenzoic acid, can migrate and rearrange the carbonyl groups of cyclopentanone to form lactones, and then the lactones can be hydrolyzed to obtain glutaric acid. In this way, the selection of peroxy acid and the optimization of reaction conditions are crucial, which are related to the yield and selectivity of the reaction.
Furthermore, glutaric acid can also be obtained by hydrolysis with glutaric acid anhydride as raw material. When glutaric acid anhydride encounters water, at an appropriate temperature and pH, the acid anhydride bond breaks and water is added to form glutaric acid. This hydrolysis reaction is relatively simple, but it is also necessary to pay attention to the acid-base balance and temperature control of the reaction system to avoid further side reactions of glutaric acid.
In addition, glutaric acid can also be synthesized by multi-step reaction with some natural products as starting materials. For example, some plant extracts or microbial metabolites can gradually construct the structure of glutaric acid through specific chemical conversion steps. However, this path often involves complex separation and purification and multi-step reaction, which requires quite high technical requirements.
All these synthesis methods have their own advantages and disadvantages, and they need to be selected according to actual needs, such as the availability of raw materials, cost, difficulty of reaction and the purity of the product.

"Tiangong Kaiwu" states that the caramel is cooked with glutinous rice or japonica rice, and brewed with malt over time. Its price in the market is difficult to determine in the past, because it varies from time to time, place and quality.
In the city of the past, if the harvest of glutinous rice and japonica rice was abundant in years, and malt was easy to obtain, the raw materials for making caramel were sufficient, the price of caramel may be slightly cheaper. However, due to the age of apology, the yield of grain is small, the raw materials are rare, and the price of caramel is high.
And in different places, the situation is also different. In places where grain production is abundant and sugar-making skills are well-practiced, the supply of caramel is sufficient, and the price may be stable and moderate. If the location is remote, the grain transportation is inconvenient, and the sugar production is difficult, the price will be high.
The quality of sugar is also related to the price. Those with pure color, sweet taste, and thick quality are the best caramel, and the price is high; those with mixed color, lack of taste, and thin quality are less expensive.
Generally speaking, in ordinary times, the price of caramel per catty in the market may be between tens and hundreds of texts. However, in case of bad weather, chaos in war, or ups and downs, it is difficult to determine the range of its price.