2-Thiazolecarboxylic acid, 4-bromo-

Mercury, the coldest, is a liquid metal. At room temperature, it is a silver-white luster, flows like beads, is heavy and sticky, and is not easy to adhere to utensils.
Its melting point is very low, only -38.87 ° C, and it easily turns into steam when heated. This vapor is colorless and odorless, but highly toxic. The boiling point is also not high, about 356.6 ° C.
Mercury has a high density, 13.59 grams/cubic centimeter, which is heavier than other common metals such as iron and copper. It has good electrical conductivity, but its thermal conductivity is inferior to most metals.
In addition, the chemical properties of mercury are relatively stable. At room temperature, it is not easy to combine with oxygen. However, when heated, it can react with oxygen to form mercury oxide. Under certain conditions, it can also chemically react with acids, alkalis and other substances.
Mercury exists in the form of mercury sulfide in Chen placer mines in nature. It is also widely used. In the past, it was often used in thermometers and sphygmomanometers to measure changes in temperature and pressure; in the chemical industry, it was also used as a catalyst; in the metallurgical industry, it can be used to extract precious metals such as gold and silver. However, due to its severe toxicity, great harm to the human body, and damage to the nervous, digestive, and immune systems, its application has become more and more cautious, and many alternatives have come into being.

Mercury (mercury) and ethanethiolic acid are both essential substances, and their chemical properties are different.
Mercury, in the form of a liquid metal, shines silver-white at room temperature, and has a high density and good fluidity. Mercury has unique chemical properties and moderate activity. In air, mercury is relatively stable and difficult to combine with oxygen rapidly. However, under heating conditions, mercury can react with oxygen to form mercury oxide, which can be recorded as:\ (2Hg + O ²\ stackrel {\ Delta }{=\!=\!=} 2Hg O\). Mercury can also form amalgamates with many metals, which makes it useful in metallurgy and other fields. In addition, mercury and sulfur can quickly combine to form mercury sulfide. This reaction is often used to treat mercury leakage to reduce its harm, that is,\ (Hg + S =\!=\!= Hg S\).
As for ethanthiolic acid, its molecule contains thiol group\ ((-SH) \) and carboxyl group\ ((-COOH) \), which gives it special chemical properties. Because of the carboxyl group, ethanthiolic acid is acidic and can be neutralized with bases. For example, it reacts with sodium hydroxide to form sodium ethanthiolate and water. The chemical equation is:\ (HSCH -2 COOH + NaOH =\!=\! The presence of sulfhydryl group makes ethanethiolic acid highly reductive and easy to be oxidized. At the same time, sulfhydryl group can participate in a variety of organic reactions, such as forming stable complexes with some metal ions, and plays a key role in chemical synthesis, medicine and many other aspects.
The chemical properties of mercury and ethanethiolic acid are significantly different due to their different structures, and each plays an important role in its own field.

In "Tiangong Kaiwu", the two uses of mirabilite and kaosan are quite extensive.
Mirabilite, its main use involves the field of medicine and industry. In medicine, mirabilite has the effect of laxative, moisturizing dryness and softening, clearing fire and reducing swelling. Ancient healers often used mirabilite as medicine to treat real heat stagnation, abdominal pain, dry stools and other diseases. In case of evidence from the Yang Mingfu, the gastrointestinal tract is dry and hot, the stool is blocked, and the abdomen is hard and painful. The combination of mirabilite and rhubarb can play the work of heat knot, so that the dry shit can be lowered, and the real heat can be drained. In industry, mirabilite can be used as a raw material for making glass. When glass is fired, glauberite can reduce the viscosity of the glass liquid, promote better melting and clarification of glass raw materials, and improve the quality and yield of glass. It is also used in the paper industry to help prepare cooking liquid, make fiber separation easier, and improve the quality of paper.
Taisha was mainly used in metallurgy and pharmaceutical processing in ancient times. In the field of metallurgy, Taisha can be used as a flux. In the process of metal smelting, the addition of Taisha can reduce the melting point of the ore, make the metal easier to separate from the ore, and improve the smelting efficiency. For example, when smelting certain refractory metal ores, Taisha can melt the ore at a relatively low temperature, reducing energy consumption. In terms of drug processing, kaosan has certain corrosiveness and toxicity. After proper processing, it can reduce toxicity and enhance curative effect. Ancient doctors used kaosan to process certain drugs to change the performance of drugs and enhance the therapeutic effect of drugs on specific diseases, such as drug processing for the treatment of scrofula, choking diaphragm and other diseases.

In "Tiangong Kaiwu", there are two methods for making candles. First, take beeswax for it. First catch wild bees, and look for a beehive in the mountains, forests and valleys. After getting the nest, steam it in a kettle, and the beeswax will come out, float on the water, and skim for later use. This wax is yellow in color and pure in texture, making it a high-quality candle material. Second, use the wax produced by ash worms. White wax worms are often parasitic on privet trees. In May, they wrap the branches with leaves and attract insects to the tree. At the end of autumn, the wax secreted by the worms covers the branches. Cut the branches and boil them in boiling water. The wax melts out and condenses into white wax. This wax is as white as snow, making candles with bright flames.
When making candles, melt the beeswax or white wax in a kettle, use cotton thread as the core, immerse it in wax liquid, and repeat several times to make the wax evenly adhere to the core. When it cools and solidifies, the candle is finished. There are also those who add spices to the wax to make the candle smell when it burns. In addition, animal oils such as butter and suet are mixed with wax to increase the toughness and flame resistance of the candle. In this way, through the processes of picking wax, melting wax, and making candles, high-quality candles can be obtained for lighting, sacrifice, etc.

Saltpeter and sulphur are both used by pyrotechnics. When storing and transporting, pay more attention to all things to ensure safety.
First, choose the place as the most important. The storage place must be dry and ventilated, avoiding moisture and hot topics. Saltpeter is dry, and if it encounters water and moisture, it is easy to deliquescent and deteriorate; although sulfur is resistant to moisture, it will be steamed by moisture and heat, or it will change. And it should not be near the source of fire. Both are easy to explode, and the candle is small, or it will cause a prairie fire.
Second, the packaging must be careful. Saltpeter should be stored in pottery urns and porcelain jars, and tightly sealed to prevent it from being too much in contact with the air and causing oxidation. Sulfur can be wrapped in cloth bags and sacks, but it should also be tight to prevent it from being scattered. During transportation, the packaging should be stable, and bumps should not be bumped to prevent damage and leakage.
Furthermore, isolation is the most important. Saltpeter and sulfur cannot be stored and transported together. The two have different properties. They are mixed and transported together, or cause chemical reactions, resulting in unexpected disasters. And the two cannot coexist with acids and alkalis. Both acids and alkalis can be combined with them, endangering safety.
In addition, personnel need training. Those in charge of storage and transportation must know their nature, understand their dangers, and be familiar with the operation method. In case of emergencies, they can deal with them calmly and take proper measures to prevent the spread of disasters.
When transporting, choose safe equipment and avoid busy cities and crowded places. If you are involved in rivers, the ship is firm and waterproof and leaking. At the storage place, set up special personnel to guard it, and patrol it frequently to check for any abnormalities. If there are any hidden dangers, get rid of it quickly. In this way, Fang Bao saltpeter and sulfur are safe during storage and transportation.