3-Fluoropyridine-2-carbonitrile

What is the main use of 3% of the 2-methyl ether in the river? There are some materials in "Tiangong Wuwu", and the use of methyl ether is also known as wood wine ether in ancient times.
First in the field of medicine, methyl ether has the effect of anesthesia. In the past, when it was necessary to treat a family's illness, methyl ether was often used to treat it. With its ability to make the patient's mind dizzy and suffer a little loss, it can be used to reduce the suffering of the patient. This is the important function of methyl ether in the Tao.
Second in the daily chemical industry. Methyl ether is very special in nature and can be used as a solution. It can dissolve many substances, so it is often used in the manufacture of materials and inks. Methyl ether is used to make it uniform on the ground. It is easy to wipe and wipe. And methyl ether has good performance, can be used quickly, and does not affect the material.
Furthermore, it is also useful in the fuel field. The fuel value of methyl ether is high, and the fuel consumption is low, and the pollution generated is less. It can be used as one of the alternative energy sources. It has its own application in ships, cooking, etc., which can help the protection of the environment, so that there is less waste and the air is fresh.
And methyl ether is also indispensable for chemical synthesis. An important raw material, with its start, can be synthesized into a variety of compounds, enriching the waste of technology, and pushing the phase of the first step.

Lead is one of the hardware. It is heavy, blue and gray in color, and has many unique physical properties.
The density of lead is quite high, far exceeding that of ordinary metals. With the density of water as one, the density of lead can reach more than eleven. When the lead block is placed in the water, it sinks to the bottom instantaneously. This characteristic makes it useful in many places where heavy objects are required, such as ballast during shipbuilding, which can ensure the stability of the ship's navigation.
The melting point of lead is low, about 300 degrees Celsius. It is heated with charcoal and can be easily melted into a liquid, which is easy to cast into various shapes. In the past, lead was often cast as lead blocks and lead strips for different needs. The boiling point of lead is quite high, reaching more than 700 degrees Celsius, so it is not easy to vaporize and dissipate under normal high temperature environments.
Lead has a small hardness, and can be left on its surface with fingernails. It is also easy to cut and hammer, and can be developed into thin sheets. This property makes it suitable for wrapping objects to prevent foreign objects from eroding.
Lead has poor electrical conductivity, which is weaker than good conductors such as copper and silver. However, in some places where insulation is required, this property is an advantage and can be used as a material for isolating current.
Lead has good corrosion resistance and is not easy to be oxidized in the air. After being left for a long time, only a layer of lead oxide film is formed on the surface, which can prevent the internal oxidation. This property makes it useful for manufacturing containers to store water, wine and other liquids.
Although lead has the above physical properties, it is toxic. If people are exposed to it for a long time or eat it by mistake, it will definitely harm the body. Although the ancients did not know its toxicology, they also saw that people who were exposed to lead often had discomfort, so they should be cautious when using it.

It is also an organic compound. Its chemical properties are particularly interesting, try to discuss in detail.
methyl ether, the molecular formula is\ (C_ {2} H_ {6} O\), the structural formula is\ (CH_ {3} OCH_ {3}\). It is common to ethers and has relatively stable properties.
In terms of thermal stability, methyl ether is quite stable to heat under normal conditions. Ordinary heating does not easily cause its decomposition. Because the carbon-oxygen-carbon bond (\ (C-O-C\)) in the methyl ether molecule is quite large, high energy is required to break this bond.
As for its reaction with acids and bases, methyl ether is difficult to react with dilute acids and bases at room temperature. However, under the action of specific strong acids, such as hydroiodic acid (\ (HI\)), methyl ether can break. Gein\ (HI\) is extremely acidic and\ (I ^ -\) nucleophilic. It can attack the carbon-oxygen bond of methyl ether, causing it to break, forming iodomethane (\ (CH_ {3} I\)) and methanol (\ (CH_ {3} OH\)).
Methyl ether is also flammable. In the air, it can burn violently in case of open flame or hot topic, generating carbon dioxide (\ (CO_ {2}\)) and water (\ (H_ {2} O\)). The chemical equation for its combustion is:\ (2CH_ {3} OCH_ {3} + 7O_ {2}\ stackrel {ignited} {=\! =\! =} 4CO_ {2} + 6H_ {2} O\). This is because the carbon and hydrogen elements in methyl ether can oxidize with oxygen, releasing a lot of heat.
In addition, methyl ether has a certain polarity due to the existence of oxygen atoms in the molecular structure, which can form hydrogen bonds with water molecules, so methyl ether has a certain solubility in water. However, the whole molecule is still dominated by non-polar alkyl groups, so the solubility is not very large.
In summary, the chemical properties of methyl ether are stable, and under certain conditions, reactions such as bond breaking and combustion can occur, which are determined by its molecular structure.

As for the synthesis of methyl ether, although the name has not been heard in ancient times, it is deduced from today's reasons, or there are various ways.
First, it can be obtained by dehydrating methanol. Methanol is a common alcohol. Under the appropriate catalyst, temperature and pressure, methanol is stripped of water between molecules to form methyl ether. If sulfuric acid is used as a catalyst to heat methanol, methanol molecules interact with each other, and hydroxyl groups combine with hydrogen atoms of adjacent methanol to form water and escape, and the rest are connected to form methyl ether. This process requires careful temperature control to prevent side reactions from occurring, if the temperature is too high, or cause other changes such as methanol decomposition.
Second, carbon monoxide and hydrogen can also be used as raw materials. Under the action of a specific catalyst, carbon monoxide reacts with hydrogen. This reaction is quite complex and requires precise regulation of the reaction conditions. The choice of catalyst is crucial, and different catalysts have great differences in reaction rate and product selectivity. Generally speaking, with metal oxides as catalysts, under appropriate temperature and pressure, carbon monoxide and hydrogen can undergo a series of reactions to form methyl ether. This way of raw materials is easy to obtain, but the reaction conditions are harsh and the equipment requirements are quite high.
Third, halogenated methane and sodium alcohol can also prepare methyl ether. Halogenated methane has high activity of halogen atoms, and sodium alcohol is alkaline. When the two meet, the halogen atom is replaced by an alkoxy group to form methyl ether. This reaction is relatively mild, but halogenated methanes are mostly toxic. It is necessary to be careful in preparation and operation, and the cost of raw materials may be high.
All these synthetic methods have their own advantages and disadvantages. Or it is necessary to consider the availability of raw materials, the level of cost, and the conditions of equipment in order to choose the most suitable method to achieve the purpose of synthesizing methyl ether.

Today, the price of rice fluctuates between the well and the market, which is related to people's livelihood. According to the market, the price of ordinary white rice is about one or two to two taels of silver per stone. However, the price of rice is not constant, and it varies with the year, supply and demand.
In a good year, the grain is abundant, the grain is abundant, and the rice source is abundant. The price is stable and slightly reduced, and the price per stone may be up to one or two or three yuan. At this time, the people are happy and their livelihood is easy.
In a bad year, natural disasters are raging, the fields are poor, and the rice source is scarce, so the price is expensive. Each stone may rise to two or two to five yuan, and even three or two taels of silver. At this time, the people are in a lot of hardship, and in order to satisfy themselves, they pour everything they have, and even sell their children and daughters, which is terrible.
There are also merchants who hoard and are curious. When they see the fluctuation of rice prices, they have ulterior motives. They stock up on rice at low prices in the year of abundance, and sell it at high prices in the year of famine, in order to make huge profits. This generation's behavior promotes the rise of rice prices, which is a disaster for people's livelihood.
Furthermore, whether the transportation is convenient or not is also related to the price of rice. Near the water pier, boats and boats come and go, transportation is convenient, the circulation of rice and grain is smooth, and the price is often stable. In remote places, traffic is blocked, and the transfer of rice and grain is difficult. The price is often higher than elsewhere.
In short, in the field of rice prices, one or two or three dollars in a good year, more than two or five dollars in a bad year, and usually about one or two or five dollars to two taels of silver per stone. However, they all change due to many reasons, and it is difficult to generalize.