5-Bromopyridine-3-carboxylic acid methyl ester

Mercury is a highly toxic metal. It is liquid at room temperature, shining with a silver-white brilliance, and is volatile. Its density is quite high, about 13.6 times that of water, and its fluidity is very good.
Ethyl acetate is a colorless and transparent liquid with a fragrant fruity aroma. Its boiling point is relatively low, about 77 ° C, and it is volatile. It is slightly soluble in water, but miscible with most organic solvents, such as ethanol and ether. Its density is less than that of water, about 0.902g/cm ³.
Mercury has many properties. Because it is volatile, it will slowly release mercury vapor at room temperature. This mercury vapor is highly toxic and can seriously damage the nervous system, kidneys and other organs when inhaled. Its liquid nature makes it flow freely. Once sprinkled, it is easy to form small mercury beads, which roll around and are extremely difficult to collect completely.
Ethyl acetate, as a common organic solvent, is often used as a solvent for coatings, inks, adhesives, etc. due to its low boiling point and volatility, which is convenient for solute dispersion and coating. Because it is slightly soluble in water and has a low density, it will float on the upper layer of water in some liquid-liquid separation operations, and can be separated according to this characteristic. And because of its pleasant smell, it is also used in food additives and other fields, and can be used as a fragrance ingredient to give products a specific aroma. However, it should be noted that ethyl acetate is flammable and should be kept away from fire sources when used.

To prepare trimethyl borate, there are various methods.
First, boric acid and methanol are used as the starting point, and sulfuric acid is added as the catalyst, and the heat is combined. In this case, sulfuric acid is the catalyst, and boric acid and methanol are formed into esters and water. The reaction formula is: $H_3BO_3 + 3CH_3OH\ stackrel {H_2SO_4} {\ rightleftharpoons} B (OCH_3) _3 + 3H_2O $. However, the reaction is reversible. To obtain more products, or increase the amount of reactants, or remove water, so that the horizontal shift to the ester can be made.
Second, boronic anhydride and methanol can be used. Boronic anhydride is first combined with water to obtain boric acid, followed by methanol, and sulfuric acid is also added to urge it, as before to form esters. < Br >
There are also those who use sodium borohydride as materials with methanol and halomethane. Sodium borohydride is first combined with methanol to generate hydrogen and boromethoxy compounds, and then with halomethane to obtain trimethyl borate. This step is a little more complicated, but it is also available in some situations.
There are also those who start with boron trichloride and sodium methoxide. When boron trichloride meets sodium methoxide, chlorine is replaced by methoxy to form trimethyl borate and sodium chloride. This reaction is faster and the product is easy to separate. Only the raw material boron trichloride is rotten and toxic, so it should be used with caution.
The methods for preparing trimethyl borate each have their own strengths and weaknesses. Users should choose according to the situation, or consider the ease of availability of raw materials, the ease of control of reaction conditions, or the purity of the product. The best method is determined by weighing.

Mercury is a highly toxic substance, and one should be careful about everything. Ethyl cyanoacetate is also a harmful substance, and its application cannot be ignored.
Mercury has been used in many fields, but due to its toxicity, its application is now limited. In the past, in the art of alchemy, alchemists wanted to seek longevity, and used mercury as a medicine, thinking that it could refine elixirs. In fact, mercury poison hurt people and caused many deaths. In ancient times, metallurgy, or mercury was used to extract gold, but the evaporation of mercury made craftsmen sick. Today, mercury is mostly used in specific experiments of scientific research, such as manometer and thermometer. However, due to environmental protection and safety considerations, it is gradually looking for alternatives.
Ethyl cyanoacetate is mainly used in the field of pharmaceutical and chemical industry. In pharmaceutical synthesis, it is often a key intermediate, used to prepare a variety of drugs, such as some analgesic and antibacterial drugs. In pesticide manufacturing, it also has its own shadow, and can participate in the synthesis of insecticides, fungicides, etc., to protect crops from pests. However, it is toxic, and its production and use must be strictly followed to prevent endangering the environment and personal safety.
These two are highly toxic metals and harmful chemical raw materials. Although they have their uses in specific fields, they should be treated with caution. They should not be ignored because of their use. When safety and environmental protection are the priority, they should be used reasonably to avoid major disasters.

The price of Guanfu's market is related to supply and demand, materials, and skills. In today's words, alum stone and ethyl acetate, if you want to know their price, you should consider everything.
Alum stone has different categories and uses. The quality of alum stone used in medicine is pure and strict, and the price must be higher than that of regular products. The difficulty of its procurement and the amount of production can determine its price. If the origin is rich and convenient, the price may be plain; if the origin is remote and the excavation is difficult, the price will rise. And the process of refining is also heavy. The alum stone of refined medicine has been purified through multiple processes, and the price is not cheap.
Ethyl acetate is commonly used in chemical industry. The price is linked to the cost of raw materials, production processes, and market demand. The price of raw materials fluctuates, and ethyl acetate follows. If raw materials are easy to obtain and cheap, the price is also flat; otherwise, it is expensive. The quality of the production process is related to energy consumption and output. The art of high efficiency reduces costs and increases efficiency, and the price may be competitive. When the market demand is high, the demand exceeds the supply, and the price must be high; when the demand is low, the supply exceeds the demand, and the price will fall.
From this perspective, if you want to know the market price of alum stone and ethyl acetate, it cannot be determined in one word. When you carefully consider the origin, supply and demand, and craftsmanship, and comprehensively weigh them, you will find the truth.

Mercury is very toxic, and it should be stored and transported with caution.
Mercury is volatile. In order to prevent it from escaping into the air and causing harm to the surrounding area, it must be stored in a sealed container. And the density of mercury is high, it is advisable to use a thick and solid container to avoid damage and leakage. The storage place should be cool and dry, protected from heat and direct sunlight, to prevent changes in the state of mercury due to temperature changes.
When transporting, the first heavy packaging should be tight. In addition to sealed containers, it should be wrapped with cushioning materials to prevent collision and damage to the container. The transporter must be professionally trained to understand the hazards of mercury and emergency measures. During transportation, you must also travel steadily to avoid bumps and vibrations.
As for ethyl acetate, it is flammable. The storage place must be kept away from fire and heat sources, and there must be good ventilation to dissipate its volatilization. Because of its volatility, the container should also be well sealed to prevent volatilization loss and gas accumulation.
When transporting ethyl acetate, the vehicles used should be equipped with fire and explosion-proof devices. When loading and unloading, handle it with care. Brutal operation is strictly prohibited to prevent damage to the container. Transport personnel should be familiar with fire response strategies and be equipped with fire extinguishers.
Both are dangerous things. During storage and transportation, relevant records must be detailed, including quantity, entry and exit time, transportation route, etc., for traceability and supervision, so that Fang Security is safe.