5-chloro-1,3-benzothiazole

In "Tiangong Kaiwu", sulfur is mixed with saltpeter and charcoal in a certain proportion to form gunpowder. Gunpowder has three main uses.
One is for military operations. In war, gunpowder can be made into all kinds of firearms, such as shot guns, artillery, etc. The shot gun is made of bamboo tube and contains gunpowder and child nest. After igniting, the gunpowder erupts and shoots the child nest, which can kill the enemy at a certain distance. This is the embryonic form of early firearms. It has a significant effect on killing the enemy on the battlefield and attacking the city. Artillery is more powerful. The artillery shells fired by it can destroy the enemy's defenses with the powerful impact of gunpowder explosion, causing mass destruction to the enemy, and greatly changing the mode of war and tactical strategy.
The second is for folk entertainment. Gunpowder is used to make fireworks. Every festive festival, fireworks bloom in the night sky, colorful and dazzling. Fireworks are made using different effects produced when gunpowder is burned, such as light, sound, color, etc. Or like silver flowers and fire trees, or like meteors flying, it brings joy and joy to the people. It has become an indispensable element of traditional festivals and carries many cultural meanings and emotional sustenance.
Third, it also plays a role in the industrial field. In the mining of ores and other aspects, gunpowder can be used for blasting. By precisely controlling the amount of gunpowder and the blasting position, hard rocks can be blasted, which is convenient for ore collection, improves mining efficiency, promotes mining development, and provides basic raw materials for subsequent industrial activities such as metallurgy to promote industrial process.

Mercury is a metallic element, its symbol is Hg, at room temperature and pressure, is a liquid state, with the following physical properties:
1. ** Color and state **: Mercury appears as a silvery white shiny heavy liquid, which is easy to flow at room temperature. As "Tiangong Kaiwu" said "Where mercury,... its shape is like water like silver, hence the name mercury", the image describes the state of mercury like water like silver.
2. ** Density **: The density of mercury is quite high, reaching 13.59 grams/cubic centimeter. Compared with common liquids, such as water, the density of mercury is much higher than that of 1 gram/cubic centimeter. In nature, mercury is often deposited in ore crevices due to its high density.
3. ** Melting point and boiling point **: Mercury has a melting point of -38.87 ° C and a boiling point of 356.6 ° C. This property causes it to be liquid at room temperature, and when heated to 356.6 ° C, it will boil and transform into a gaseous state.
4. ** Volatility **: Mercury is volatile to a certain extent. Although the volatilization rate is slow, it is easy to form mercury vapor in specific environments, such as high temperatures and poor ventilation.
5. ** Solubility **: Mercury is insoluble in water and organic solvents, but soluble in certain strong acids such as aqua regia and concentrated nitric acid.
6. ** Conductivity **: Mercury is a metal with good conductivity and can act as a conductor in circuits.
7. ** Surface tension **: Mercury has a high surface tension, and dripping on a flat table will form nearly spherical droplets, which are not easy to spread out.

Mercury is a metallic element with the chemical symbol Hg. It is liquid at room temperature and is the only liquid metal. 1,3-butadiene is an organic compound with a conjugated double bond structure. The chemical properties of the two are quite different.
Mercury has relatively stable chemical properties and does not react with oxygen at room temperature. When heated, it can combine with oxygen to form mercury oxide. Mercury can react rapidly with sulfur elemental matter to form mercury sulfide, which is often used to treat mercury leakage. Mercury can also form amalgams with various metals and has applications in metallurgy and other fields. Due to its liquid properties, mercury has a high surface tension and rolls in a spherical shape. Mercury and its compounds are toxic and highly harmful to the environment and human body.
1,3-butadiene is prone to addition reactions due to its active chemical properties due to conjugated double bonds. For example, it can undergo 1,2-addition or 1,4-addition reactions with bromine elemental substances to generate different products. Under certain conditions, 1,3-butadiene can also polymerize to form poly-1,3-butadiene, which is an important raw material for synthetic rubber. 1,3-butadiene is flammable and can form explosive mixtures when mixed with air. In case of open flame and high heat, it can cause combustion and explosion.
Mercury is a metal element, and its chemical properties are mainly stability and reaction with specific substances; 1,3-butadiene is an organic compound. Due to the conjugated double bond structure, the addition and polymerization reactions are prominent. The chemical properties of the two are quite different, and each plays a unique role in different fields. At the same time, it also has different effects due to its own characteristics.

The combination of saltpeter and sulphur with charcoal to make gunpowder is a wonderful method in ancient China. As for the use of saltpeter, sulphur and charcoal to make gunpowder, there are various methods.
First, the selection of materials is the key. Saltpeter needs to be pure and pure, with a white color like frost and no variegated impurities. Sulphur should also be pure in quality, with a yellow and moist color. Charcoal should be fired from hardwood, such as birch and willow, etc., to make charcoal, and grind it into fine powder, with an even thickness, to obtain a good material.
Second, the method of compounding. The wise man of ancient times has obtained an exquisite ratio through repeated experiments. About the ratio of saltpeter seven, sulfur one, and charcoal two is summed up. This ratio is non-stereotypical, depending on the use, season, climate, etc. There is a slight profit or loss. Such as for fireworks, or to increase the amount of sulfur to make the flame gorgeous; for firearm firing, or to adjust the degree of saltpeter to increase the power of medicine.
Third, the method of mixing. Place the selected saltpeter, sulfur, and charcoal in a stone mortar or a wooden trough in proportion. First, use the pestle and mortar to gently mash. When initially mixing, the force should be slow to prevent it from igniting quickly. Then grind it with stone grinding or special utensils, so that the three are fully mixed and uniform as one.
Fourth, the method of making the type. After mixing, if it is loose medicine, it can be stored in a clay pot and sealed to prevent moisture. If you want to make it into a granular medicine, use water or rice soup as a binder, mix it with the powder, and rub it into granules. The size of the granules varies according to the use. Small ones are like corn, used for bird guns; large ones are like beans, used for artillery. After making, dry in the shade or dry, and store in a dry place.
The making of gunpowder is related to the safety of the family and the country, and the brilliance of fireworks. All kinds of methods are the crystallization of the wisdom of the ancients. Later generations should treasure and pass it on, and use it wisely to benefit the family and the country.

Both saltpeter and sulphur belong to the genus of medicinal stones, and their price in the market often varies with time and place.
In today's world, the price of saltpeter is about one tael to three taels of silver per catty. However, this is not the exact number. If the origin is close and abundant, the price may be slightly reduced; if the journey is difficult, the price may increase. And the purity of its quality is also related to the level of the price. Those with pure quality, the price is high; those with miscellaneous, the price is slightly inferior.
As for sulfur, its market price is between half and half of silver per catty. Sulphur is widely used in medicine, alchemy, etc. The difficulty of its refining, the amount of supply and demand, can make the price fluctuate. If refining is easy and supply exceeds demand, the price will fall; if refining is difficult and there are many people in need, the price will rise.
Both of these are precious things, and they are of great use in alchemy, pharmaceuticals, and various processes. Although the market price is constant, it is easy to change from time to time, and it should not be stuck in the words.