6 Iodopyridin 3 Amine

Arsenic is a highly toxic substance with unique chemical properties. The main component of arsenic is arsenic trioxide ($As_2O_3 $).
This arsenic trioxide is an amphoteric oxide. When it encounters acid, it can react with it. In the case of hydrochloric acid, it is generally difficult to react because its acidity is relatively weak; however, in the case of strong acids such as nitric acid, under specific conditions, arsenic trioxide can be oxidized to form corresponding arsenate.
When arsenic encounters alkali, it is very easy to react. Arsenic trioxide can react with bases such as sodium hydroxide to form arsenite and water, which is a typical reaction of acidic oxides and bases.
From the perspective of redox, arsenic trioxide is + 3 valent, which is in the intermediate valence state, so it is both oxidizing and reducing. Under the action of suitable reducing agents, the valence of arsenic can be reduced and reduced. For example, in an acidic environment, it can be reduced to elemental arsenic by hydrogen sulfide. In the case of strong oxidizing agents, such as potassium permanganate, the valence of arsenic can be increased and oxidized to + 5 valent arsenic.
In addition, although arsenic has a small solubility in water, it can also be partially dissolved, and the dissolved part will be hydrolyzed, making the solution slightly acidic.
Because of the strong toxicity of arsenic, it was often used by outlaws as a poison to murder others in ancient times. The principle of its toxicity lies in the fact that when arsenic trioxide enters the human body, it can combine with the thiol group of proteins, interfering with the metabolic process of cells, especially causing serious damage to the nervous system, digestive system and cardiovascular system, causing human dysfunction and endangering life.

There are various common methods for making nitrate. The first is the method of frying, gathering and frying in the soil containing nitrate. First dig the ground into a pit, take the soil in it, pour water into it, so that the nitrate dissolves in the water. Then take the water, put it in a kettle, and fry it with fire. The water gradually evaporates, and the nitrate is dissolved at the bottom of the kettle. Ancient craftsmen often used this method to find fertile soil containing nitrate in remote parts of the wilderness. After this process, they obtained nitrate and used it.
The second is the leaching method. Choose a stone containing nitrate, or old wall soil, etc. Build a tank to place the stone and soil, and drizzle it with water. The water seeps through the stone and soil, carries the nitrate down, and collects the water. After evaporation and concentration, the nitrate can be obtained. This method uses the power of water to separate nitrate from stone and soil, which is quite ingenious.
The third is the freezing method. In the cold winter, if there is nitrate water, it is placed outside, and the nitrate crystallizes when it is cold. Because nitrate changes in solubility at low temperatures, it precipitates from water. This method is also a good strategy to take advantage of the time to save the trouble of frying.
There is also a metathesis method, which uses other things and things containing nitrate to react and synthesize nitrate according to chemical principles. Although there are few records in ancient times, this method has gradually flourished in later generations. It uses the wonders of chemical changes to precisely make nitrate, and the resulting nitrate is purer.
All these methods were condensed by the wisdom of the ancients, either by the power of water and fire, or by the change of time, or by the combination of things, so that nitrate could be used for purposes, and made great contributions to various industries such as fireworks and medicine.

Eh, sulfur and sulfur are useful in any field. Sulfur is used in many fields.
The first chemical field is promoted. Sulfur is the main material of sulfuric acid, and sulfuric acid is used in chemical industry. It is used in fertilizers, chemical industry, petroleum refining and other fields. Such as chemical fertilizers and phosphorus fertilizers, sulfuric acid and phosphorus stone need to be reversed in order to obtain phosphorus fertilizers that can be used to promote production.
Furthermore, metallurgical fields are also indispensable. Metallurgical, thermal, and other metals, sulfur can be used as a melting aid, reducing the melting of stone, promoting the separation of gold and stone, improving the degree and efficiency of metallurgy.
And in the field, sulfur also has its work. Sulfur has the effect of bacteria and scabies, and is often used to treat skin diseases. It can heal scabies, rashes and other diseases, and make people's muscles healthy.
Rubber also produces sulfur. Vulcanization treatment can make rubber more durable, wear-resistant and resistant. The rubber of the rubber, because of vulcanization, is durable and safe.

It is one of the essential elements for sulfur plant growth. It can synthesize plant protein, help plant replacement, and supply sulfur, which can promote plant health and increase crop yield.
In addition, in food production, sulfur can be used for preservative and bleaching. For example, some preserved fruits are processed by sulfur fumigation to retain color and prevent corrosion and extend the shelf life of food. However, the dosage should be in accordance with the standard, so as not to harm people.
In addition, sulfur is used in many fields such as chemical industry, metallurgy, rubber, rubber, food, etc., all of which are in an important position, and the people's livelihood and production are very dense.

In today's market, the price of melons varies from time to time, and also varies according to quality and land.
When spring comes, all kinds of things begin to be sold, but melons are not yet in full bloom, and their price may be high. At that time, there were few melons, and there were many seekers, and merchants could live in rare goods, so the price was high. Most of the melons in the city are shipped from far away. The journey fee is not only complicated, but the cost also increases, and the price is not cheap.
From summer to the month, melons are ripe and fall, and the fields are full of them. At this time, the output of melons has increased greatly, and they fill the city. Farmers compete for sales, and merchants compete to sell. In order to sell quickly, the price is falling. Ordinary melons are cheap and high quality, and the common people can buy them and eat them to relieve the heat. Such as rural markets, the price of melons is particularly low, because the origin is close, eliminating the cost of transshipment.
As for the quality of melons, it is also related to their price. Those with thin skin and sweet flesh and rich juices must be higher than those of regular melons. If the melon is well-shaped and bright in color, it can also increase its price. And famous melons, such as the best melons produced in a certain place, have a long reputation and are expensive.
Furthermore, the distance and proximity of the place have a great impact on the price of melons. In the capital city, in the prosperous place, the price of melons is high, and the price of melons follows. And in remote towns, the price of melons may be slightly lower. However, if the weather is unfavorable, such as drought and flood disasters, the harvest of melons will be damaged, and the price may rise even in the place of origin.
Generally speaking, melons are expensive in spring, and melons are cheap in summer; melons of good quality are expensive, and melons of regular taste are cheap; melons in the city are expensive, and melons in the countryside are cheap. However, the market conditions are ever-changing, and the price of melons is also impermanent, depending on various causes.

The Book of Heavenly Works states: "Burnt stone turns into ash, and its quality is used in the square book, and there are genera of lime, oyster ash, and kiln ash." The lime and oyster ash involved in this are all products of burnt stone, and their storage conditions are also exquisite.
Lime is made of burnt limestone. Its nature is intense, and it boils in contact with water to form slaked lime. When stored, it needs to be placed in a dry place, protected from water and moisture. If it is invaded by moisture, it will dissolve and lose its effectiveness. Because lime is very easy to chemically react with water, it turns into slaked lime and releases a lot of heat. Therefore, it should be stored in a closed container, so that it does not come into contact with external moisture, so that it can be stored for a long time without losing its properties.
Oyster ash comes from the shell of an oyster. After burnt, its properties are also dry. When storing, it should also choose a dry place. Although its moisture-proof performance is slightly better than that of lime, it should not be neglected. After the oyster shell is burnt, its texture still has a certain water absorption. If it is in a humid environment for a long time, it will also be wet and deteriorate. Therefore, it should be stored in a sealed container such as an urn and a jar, and placed in a highly dry place to prevent moisture from penetrating.
Kiln ash is the ash left after burning coal or firewood in the kiln. This ash also has the property of dryness and dampness, and can be used for some purposes. It should be stored away from water sources and should not be coexisted with perishable materials. Because it is alkaline to a certain extent, it may cause corrosion to other items. Packed in a clean bag and placed in a ventilated and dry place, its quality can be guaranteed for a long time.
All this burnt stone is of its own nature. When storing, it is necessary to pay attention to drying and sealing to prevent deterioration and failure, so that it can play its due effect when used.