1-Bromo-4-Iodo-2-Methylbenzene

Xylene is also an organic compound. It has special physical properties and is worthy of detailed investigation.
Looking at its shape, under room temperature and pressure, xylene is a colorless and transparent liquid, with a clear texture, an aromatic taste, and a specific smell. Although this smell is not as pungent as a stench, it is also different from a pleasant fragrance. If you smell it for a long time, it may disturb human health.
As for its volatility, xylene evaporates quite quickly. Because its boiling point is relatively low, between 137 ° C and 144 ° C, it is easy to convert from liquid to gaseous in ordinary environments and escape into the air. This property makes it easy to form a flammable mixture of steam and air in chemical production, storage and use places, and there is a risk of fire and explosion.
Furthermore, in terms of density, the density of xylene is slightly less than that of water, about 0.86 g/cm ³. This property makes it difficult to settle if it accidentally leaks on the water surface, it will float on the water, diffuse with the water flow, and it is difficult to settle. Because it is volatile, it diffuses more rapidly, increasing the difficulty of treatment.
In terms of solubility, xylene is insoluble in water, but it can be miscible with organic solvents such as ethanol, ether, and chloroform. This property makes it used in the field of organic synthesis, often as a solvent, and can dissolve many organic substances, which can help the progress of chemical reactions.
The physical properties of xylene play a key role in chemical production, scientific research experiments and daily applications. Understanding its properties can help to avoid risks and promote the development of various industries, and also ensure the safety of the environment and human beings.

Ethane is a genus of alkanes, the simplest chain hydrocarbons containing carbon-carbon single bonds. Its chemical properties are as follows:
1. ** Stability **: Under normal conditions, ethane is quite stable, and it is difficult to react with strong acids, strong bases, and strong oxidants (such as acidic potassium permanganate solution). This is because the bond energy of carbon-carbon single bonds and carbon-hydrogen bonds in ethane is relatively high, and the structure is stable. Just like "Tiangong Kaiwu", many substances in the world have their own inherent properties, and they are not easy to change in normal times.
2. ** Oxidation reaction **: Ethane can burn in oxygen, emit a light blue flame, generate carbon dioxide and water, and release a lot of heat. The chemical equation of the reaction is $2C_ {2} H_ {6} + 7O_ {2}\ stackrel {ignited }{=\!=\!=} 4CO_ {2} + 6H_ {2} O $. This reaction is like everything in the world can be changed under suitable conditions. Ethane encounters oxygen and is ignited by the opportunity to produce a violent oxidation reaction, releasing energy.
3. ** Substitution Reaction **: Under light conditions, ethane can be substituted with chlorine, and chlorine atoms gradually replace hydrogen atoms in ethane molecules to form various products such as chloroethane. For example, $C_ {2} H_ {6} + Cl_ {2}\ stackrel {light }{=\!=\! =} C_ {2} H_ {5} Cl + HCl $. This reaction is like a clever replacement. In the special environment of light, the chlorine atom of chlorine gas and the hydrogen atom of ethane are replaced with each other, and different substances are derived. As recorded in Tiangong Kaiwu, under specific conditions, substances interact to produce new forms and properties.

"Tiangong Kaiwu" contains that when Yi Geng is the age, the yellow bell is the palace, the terracotta is the Shang, the Gu Shu is the horn, the Lin Zhong is the Wei, and the Nanlu is the feather. It involves the knowledge of Lulu, and in the year of Yi Geng, the first rhythm is the yellow bell, which plays an important role in the construction of the music rhythm system.
The yellow bell is the first of the twelve rhythms of ancient music rhythm, and its role is very important. As far as the music rhythm system is concerned, it is the basis for determining the relative relationship between pitch and each rhythm. In the year of Yi Geng, setting the yellow bell as the palace is like establishing the cornerstone of the music building. The other rhythms are derived according to them. Taichu, Gu Hua and other rhythms form a specific interval relationship with the yellow bell, and together build a complete musical rhythm structure, so that the music has a harmonious and orderly pitch organization.
From the perspective of scale composition, when the yellow bell is the palace, it determines the beginning and core position of each note in the scale. In traditional music performance, the scale determined based on this rhythm can produce a unique musical style and emotional expression. For example, the tunes created on this basis are either solemn and solemn, or elegant and peaceful. The palace sound of the yellow bell is like the axis that dominates the direction of the melody, so that the progress and turns of music are carried out around it.
Furthermore, in ancient music culture, the yellow bell is not only related to the rhythm, but also closely related to the calendar, solar terms, etc. The ancients believed that the rhythm of music corresponds to the natural laws of heaven and earth. As the first rhythm, the yellow bell symbolizes the beginning of all things and the generation of yang, which has profound cultural symbolic significance. In the year of Yi Geng, the yellow bell started with the yellow bell, which contains the cultural concept of conforming to nature and the unity of man and nature, and integrates music into the laws of heaven and earth. In short, the yellow bell plays multiple key roles such as cornerstone, core and cultural symbol in ancient music rhythms and related cultural systems.

The synthesis of methylamine, through the ages, there are many wonderful methods. In the past, there was a method of reacting alcohol and ammonia in the gas phase. First take an appropriate amount of alcohol, put it in a special vessel, pass ammonia, add appropriate temperature and pressure, and add a suitable catalyst, then methylamine is formed. The reason is that the hydroxyl group of the alcohol is replaced by an amino group, and after complicated chemical changes, methylamine is finally obtained.
There are also those who use halogenated hydrocarbons and ammonia as raw materials. When the halogenated hydrocarbon encounters ammonia, the halogen atom interacts with the nitrogen atom of the ammonia, the halogen ion leaves, and the nitrogen atom is connected to the hydrocarbon group to form methylamine. This process requires careful temperature control and reaction progress to prevent side reactions from occurring in order to increase the yield of methylamine.
Furthermore, formaldehyde and ammonium formate are used as the starting materials, and the two interact under specific conditions. The carbonyl group of formaldehyde reacts with the amino group and hydrogen of ammonium formate in a series of reactions, during which the chemical bonds are broken and recombined delicately, and finally polymerized into methylamine. This approach requires strict reaction environments, such as pH, temperature and other factors. A slight difference will affect the quality and quantity of the product.
Another is made of carbon monoxide, hydrogen and ammonia. With the help of a catalyst, carbon monoxide and hydrogen are first synthesized into methanol intermediates, and methanol reacts with ammonia. After ingenious transformation, methylamine is obtained. This method requires precise regulation of the reaction parameters to make each step of the reaction smooth, so as to achieve the purpose of efficient synthesis of methylamine.
All these synthesis methods have their own advantages and disadvantages. It is necessary to consider the availability of raw materials, the level of cost, the purity of the product and other factors according to actual needs, and make careful choices before making good use of them to form methylamine.

Mercury is the most toxic thing. Methyl mercury is especially treacherous. When storing and transporting, many matters must be taken with caution.
First of all, it is clear that methyl mercury is highly volatile and can escape into the air at room temperature. Therefore, when storing, it is necessary to choose a closed container, and the material must also be carefully selected, such as glass, polytetrafluoroethylene, to prevent the leakage and volatilization of mercury. And the container must be placed in a cool, dry and well-ventilated place, away from heat and fire sources. Due to the increase in temperature, it will evaporate quickly, resulting in a sharp increase in danger.
When transporting, tight packaging is essential. In addition to airtight containers, cushioning materials need to be supplemented to prevent damage to the container due to bumps and collisions. And transportation vehicles must also be equipped with corresponding emergency equipment, such as adsorption materials, protective gear, etc., in case of emergencies.
Furthermore, methylmercury is highly lipid-soluble and can easily penetrate biofilms and accumulate in organisms, thus endangering ecology and human health. Therefore, storage and transportation places should be kept away from water sources and residential areas to prevent accidental leakage and harm to the common people. Employees must also undergo strict training, be familiar with operating norms and emergency response methods, wear professional protective equipment, and avoid direct contact.
All of these are what should be paid attention to when storing and transporting methylmercury. A little sparse, it may lead to a catastrophe, endangering the balance of the ecology, and endangering the well-being of all people.