1 Bromo 3 Iodo 4 Fluoro Benzene

Mercury is very soft and good at flowing. It is a liquid at room temperature, with a silver-white color and a metallic luster. Its density is quite high, about thirteen times that of water. And mercury is very volatile and can gradually dissipate in the air. This characteristic cannot be ignored.
The chemical activity of mercury is medium among metals, and it can react with many non-metallic elements. In case of sulfur, the two quickly combine to produce mercury sulfide, which is the main component of cinnabar. This reaction is often used to remove mercury.
Mercury can also interact with oxygen. When heated, mercury combines with oxygen to form mercury oxide. This is an important chemical reaction, which was involved in many ancient alchemists.
Furthermore, mercury can form amalgams with a variety of metals, such as gold and silver, and the formation of amalgams is often used in metallurgy and other fields.
However, mercury and its compounds are many toxic and can invade the human body through the respiratory tract, skin and digestive tract, damaging the nervous system, kidneys and other important organs. Therefore, when using and disposing of mercury, be careful and strictly abide by the regulations to prevent mercury damage.
Finless porpoises are gentle and agile, living in freshwater waters, especially in slow streams and shallow beaches. Their body color is gray, dark on the back, slightly light on the abdomen, and their body is elegant and streamlined, which is conducive to smooth swimming in the water.
The finless porpoise has keen senses and an exquisite echolocation system, which allows it to accurately hunt in muddy waters. Its diet is dominated by aquatic creatures such as small fish, shrimp and crabs, and when it preys, it moves quickly and efficiently.
Although the finless porpoise is a mammal, it has lived in water for a long time and has evolved physiological characteristics to adapt to aquatic life. When it breathes, its head sticks out of the water and its movements are light. Its reproductive cycle is relatively long, and each litter produces one more calf, which takes good care of the young.
However, at present, the survival situation of finless porpoises is worrying, and factors such as water pollution, overfishing, and busy shipping all threaten their survival, causing their population to decline sharply. We should do our best to protect them and keep them alive in rivers.

To make a compound of alum, nitrate and sulphur, there are many methods, each with its own strengths, and needs to be selected according to different purposes and conditions.
The alum is mostly obtained from calcination of aluminium stone. Choose high-quality aluminium stone, crush it into small pieces, put it in a ceramic crucible, and calcinate it with fierce fire. When its color turns white and the texture is loose, it is calcined alum. After water quenching, filtering, evaporation and crystallization, pure alum can be obtained.
The preparation of nitrate is often derived from nitrate soil. Excavate the soil containing nitrate, rinse it with water, and obtain nitrate water. The nitrate water is stored in a large kettle, heated and evaporated until crystals precipitate, which is coarse nitrate. The method of recrystallization is used to obtain refined nitrate in addition to its impurities.
Sulfur is obtained, or it is roasted from pyrite. Sulfur-rich pyrite is selected and roasted in a special furnace at an appropriate temperature. Sulfur is sublimated by heat and collected by condensation to obtain sulfur.
Three-compound medicine, if it is gunpowder, according to the ancient method, mix nitrate, sulfur and alum in an appropriate proportion. First grind the nitrate finely and sieve it to remove its coarse grains. Sulfur is also ground to very fine, and mixed evenly with the nitrate. Alum is also processed into a fine powder, slowly added, and stirred to mix well. The mixing process must be careful to prevent its heating and friction from causing accidents. < Br >
Or when compounding the drug, first dissolve the alum into a solution with an appropriate amount of water, slowly add it to the mixture of nitrate and sulfur, and stir it while adding to make the drug blend better. When the water dries gradually, the drug becomes loose, and then dry it, but the drying temperature should not be too high.
To make this compounding drug, the details of the process are crucial. The accuracy of the ratio, the uniformity of mixing, and the caution of operation are all related to the quality and effectiveness of the compounding drug.

Alas, now ask where mercury, alum, nitrate, and sulphur are useful, and I will come to the way in detail.
Mercury is widely used in alchemy rooms. Ancient alchemists, who desire longevity, refined alchemy pills, and mercury was often used for them. Mercury cover is flexible and changeable, and in alchemy techniques, it is often the key to causing various changes. And in the field of medicine, it is also involved. In the past, those who used mercury and mercury compounds as medicine should be used with caution, because its toxicity should not be underestimated.
Alum is useful in dyeing workshops. It can be used as a mordant to help the fabric color evenly and firmly. It also has strengths in water purification. Putting it into water can make the impurities in the water condense and settle, making the water clear and easy to use. And in food processing, it was used a little in some food production in the past to enhance its taste and texture, but now it is also necessary to follow the system to prevent excessive damage.
Nitrate is important in the military. The system of gunpowder, nitrate is an important thing. Mix with sulfur and charcoal in a certain proportion to make gunpowder, which can burst out of great power. In war equipment, such as artillery, guns, etc., all rely on this to exert their power. In medicine, it is also recorded, or it can be used as medicine, with the functions of clearing away heat and reducing swelling. However, it is necessary to follow the medical instructions.
Sulfur is commonly used in alchemy by fire. Combined with mercury, etc., it can produce various medicinal pills. In medicine, its warm nature can be used for the treatment of certain diseases of deficiency and cold, and it can also kill insects and relieve itching. It can also be used externally to treat scabies and other diseases. In industry, it can also be used as a vulcanizing agent for rubber, so that the properties of rubber can be improved.
Where mercury, alum, nitrate, and sulfur are used in various fields, each has its own ability. When they are used, they should be prudent, understand their advantages and disadvantages, and follow the path to avoid their harm.

"Tiangong Kaiwu" is a scientific and technological masterpiece written by Song Yingxing in the Ming Dynasty, in which the description of things is accurate and detailed. The physical properties of river clams, clams, and razors can be viewed from the following aspects:
The first word of river clams, its shell is hard, mostly oval-shaped, and the surface of the shell often has a ring-like texture. This is the trace of time, just like the annual ring of a tree, which can help to infer its growth age. The color of the shell is diverse, or blue-gray, or brown-brown, depending on the environment of the living water. The shell has a pearl layer, which is smooth and warm, with a beautiful luster. This layer can secrete substances to wrap foreign bodies, and form pearls over time. The flesh of river clams is soft and has a certain toughness. They move slowly in the water with axe feet, breathe with gills, and filter food from the water.
As for the clam, its shell is huge and heavy, and it is the larger of the bivalve shellfish. The shell surface is rough, with deep radiating ribs, and the shape is like the rut print of the ancient wheel, hence the name. The shell of the clam is rich in color, and the common ones are white, yellow, and brown, etc. Some varieties also have brilliant patterns on the shell surface. Its shell is hard and can be used as a raw material for decoration and handicrafts. The body of the clam is also relatively large, and it coexists with Zooxanthellae. Zooxanthellae provide nutrients for clam through photosynthesis, while clam provides a living environment for Zooxanthellae.
The shell of the clam is thin and brittle, with a long strip shape and slightly pointed ends. The shell color is mostly light yellow or brown yellow, and the surface is fine with growth lines. The razor has well-developed axe feet, which can quickly dig sand and hide in sandy or muddy flats. Its meat is tender, with high water content and delicious taste. The razor razor feeds on plankton and organic debris in the water by relying on water pipes in and out of the water, and breathes through its gills.
Although these three are all shellfish, they have their own physical properties and play different roles in the natural ecosystem, showing the wonder of biodiversity.

As for the preservation conditions of mercury (mercury) and tin in "Tiangong Kaiwu", the book states: "Mercury is the most flexible, unpredictable, and often wants to fly, so it must be sealed and stored deep, and it should not be discouraged. Its utensils should be made of porcelain urns, thickly coated with lacquer, so that there is no danger of leakage. And it should be placed in a cellar, protected from the heat of the sun, so that it can be stored for a long time."
As for tin, "Tin is soft and brittle in nature, and it is afraid of cold and moisture. The way of hiding, choose a place that is high and dry, and do not let it be close to water. If it is an utensil, be careful when using it, and do not let it collide to prevent its damage."
Mercury is volatile due to its active properties, so it needs to be packed in a well-sealed porcelain urn, and the porcelain urn should be thickly painted to prevent leakage, and stored in a cool place such as a cellar to avoid sunlight and heat, so that it can be stored for a long time. Tin is soft and brittle, and it is afraid of cold and moisture. The storage place should be a dry place at a high place to avoid close to water sources. If it is made into an appliance, be careful when using it to prevent damage caused by collision. In this way, both mercury and tin can guarantee their quality and condition to a certain extent.