3-pyridinemethanol, 2-chloro-5-fluoro-

Mercury, bromine, and iodine are all halogen elements, among which mercury is the only metal that is liquid at room temperature, while bromine is also liquid, but it is a non-metal, and iodine is a solid non-metal. Halogen elements are chemically active and often exhibit strong oxidizing properties in chemical reactions.
As far as sodium halides are concerned, sodium halides (such as sodium chloride, sodium bromide, and sodium iodide) are ionic compounds with the characteristics of typical ionic crystals. Its chemical properties are stable, easily soluble in water, and aqueous solutions can conduct electricity. Take sodium chloride as an example, it is widely used in daily life, such as seasoning, chemical raw materials, etc.
In sodium halides, the reductivity of halogen ions gradually increases according to the order of fluoride ions, chloride ions, bromine ions, and iodine ions. This means that iodine ions are more likely to lose electrons and be oxidized than bromine ions and chloride ions, while chloride ions are relatively difficult to oxidize. This is because as the radius of halogen ions increases, the attraction of atomic nuclei to outer electrons decreases, and electrons are more likely to be lost.
In chemical reactions, sodium halide can react with a variety of substances. For example, sodium chloride can be co-heated with concentrated sulfuric acid to produce hydrogen chloride gas. This reaction takes advantage of the difficult volatility of sulfuric acid and the volatility of hydrogen chloride. When sodium bromide and sodium iodide react with concentrated sulfuric acid, due to the strong reductivity of bromine ions and iodine ions, not only will hydrogen bromide and hydrogen iodide be formed, but also further oxidized by concentrated sulfuric acid to bromine and iodine. Overall, sodium halide has important uses in many fields such as chemical industry, medicine, and daily life. Its chemical properties not only show the commonality of halogen elements, but also vary due to different halogen ions.

Mercury, lead, and arsenic are common toxic and harmful elements, which are distributed in the natural environment and human activities. The following is a brief description of its common uses:
Mercury, also known as mercury, is liquid at room temperature and has a metallic luster. In ancient times, it was often used in alchemy and the production of medicinal pills. The ancients believed that mercury could be obtained from the elixir of immortality after special refining. Many emperors were enthusiastic about this. For example, Qin Shi Huang searched for alchemists to refine medicinal pills containing mercury. And mercury was also used in ancient metallurgy. It can dissolve a variety of metals and is used to extract precious metals such as gold and silver. In addition, mercury is also used to make thermometers, barometers and other instruments because of its liquid and thermal expansion and contraction characteristics.
Lead has a soft texture and good corrosion resistance. In ancient times, lead was often cast as currency, such as lead money, which was circulated and used in specific historical periods. At the same time, lead is also used to make all kinds of containers. However, due to the toxicity of lead, long-term use of lead-containing containers can easily lead to lead poisoning. In addition, lead can be used in building materials, such as lead plates, which are often used for waterproofing, radiation protection and other projects.
Arsenic, a wide variety of compounds, including arsenic trioxide, that is, arsenic, is extremely toxic. Although it is a poison, in the field of ancient Chinese medicine, after special processing, a small amount was also used to treat scabies, syphilis and other diseases. In addition, arsenic compounds have also been used to make pigments, which can add unique colors to paintings, ceramics, etc. < Br >
However, it should be noted that although these elements have their uses, they are all toxic. Long-term exposure or ingestion can cause serious damage to human health and cause various diseases. Therefore, extreme caution should be taken when using them.

To prepare dihydro, pentene and trialkyne methyl ether, you can follow the following ancient method:
First take an appropriate amount of raw materials, and use the method of precision, select the pure one to use. In a special kettle, add the reactants in sequence. The first dose of alkenes with suitable activity, followed by the raw materials of alkyne, and control the proportion of alkenyne accurately. When the amount of alkenyne is suitable for the given number, do not overdo or underdo it.
When heating up, it should be slow and uniform, so that the temperature in the kettle gradually reaches a suitable environment. This temperature is very important. If it is too high, the reactants will be easily disproportionated, and if it is too low, the reaction will be slow and difficult. Use the charcoal fire as the heat source, observe the color of the heat, and adjust the density of the charcoal to ensure that the temperature of the kettle is stable at the required degree for the reaction.
Add a specific catalyst, this agent can promote the speed of the reaction, but the amount also needs to be carefully weighed. If there is less catalyst, it will not help enough, and if there are more, it may lead to side reactions. After adding it, close the mouth of the kettle to prevent its gas leakage, so that the reaction can be carried out under constant pressure.
During the reaction, a special device is often used to probe the feelings in the kettle, observe the change of the reactants, observe the color, smell the smell, and rely on experience and skills to measure the progress of the reaction. When the reaction is approaching completion, the product is liquefied and precipitated by condensation, and then its impurities are analyzed by fractionation to obtain a pure methyl ether product.
The whole process requires the craftsman's full attention and skill. Every step is related to success or failure. If there is a slight mistake, all previous efforts will be wasted.

I look at what you are asking, is to find the price range of ethylene silk from the sea, river, and Xiang in the market. However, this matter involves many factors, and it is difficult to determine the number.
Let's talk about sea silk first, its texture may vary depending on the sea area. If it is obtained from the deep sea and is finely harvested, its price must be high, or it can reach a thousand gold; if it is produced in ordinary shallow seas, the workmanship is mediocre, and it also requires hundreds of gold.
As for river silk, the water quality of the river and the food of silkworms all affect the quality of silk. River silk woven in clear water and fertile soil to raise silkworms is delicate and shiny, and it is worth a lot, or it can reach seven or eight hundred gold; if the water source is dirty and the cocoon is not good, its price may only be two or three hundred
Let's talk about the ethylene silk again. If the ethylene silk is exquisite in craftsmanship, unique in color, and loved by people at the moment, the price may exceed a thousand gold; if the ethylene silk is slightly inferior, the craftsmanship is ordinary, and the price may be five or six hundred gold.
However, there is no constant price in the market, and it also changes with supply and demand, seasons, and fashions. When merchants gather and demand is strong, the price will rise; when the harvest is bumper in the season and supply exceeds demand, the price may fall. And the trend changes, people's preferences change suddenly, and the price of silk is also influenced by it. Therefore, if you want to know the exact price range, you need to go to the market in person and observe the changes in the market before you can get it.

The sea is vast, nurturing all things; the river is galloping endlessly, moisturizing the four directions; the lake is quiet and tranquil, nourishing life. At the three places of salt, river and lake, there are many people in the salt making and silk weaving industries.
Let's talk about the salt place first. Here are the Su family and the Zhang family. The Su family has used salt making as an industry for generations. When the salt method was first developed, their ancestors joined this industry. After several generations of research, they improved the method of salt making. The salt produced is white and evenly grained, and the salty fragrance is pure. It sells well in various places. The Zhang family is not inferior. With their keen market insight, they have opened up new sales channels, so that salt goods can reach foreign lands and become rich.
As for the river, the Li and Wang families are famous far and wide. The Li family is a silk weaver, and the silk brocade reeling skills at home are exquisite. The brocade weaved is beautifully patterned and delicate in texture. It is often favored by officials and nobles and is regarded as a treasure. The Wang family attaches great importance to business and sells silk fabrics in various places. With honest management, they have accumulated thousands of family wealth. The name of their business is known to everyone.
At the lake, the Chen and Zhao families are industrial giants. The Chen family is good at raising silkworms, and has unique methods for silkworm seed selection and mulberry leaf cultivation. The silk produced is flexible and slender, and of high quality. It is a good product for silk weaving. The Zhao family is skilled in weaving craftsmanship, and their fabrics are not only highly praised in China, but also sold overseas with merchant ships, contributing greatly to the local economic prosperity.
These several families are on the banks of salt, rivers and lakes. With hard work and wisdom, they have flourished the industry and flourished the economy, becoming leaders in one party, and their achievements have been passed down by future generations.