Inorganic compounds usually refer to compounds that do not contain carbon elements but include carbon oxides, sulfides, carbonates, cyanides, carboranes, carbonyl metals, and other carbon-containing compounds studied in inorganic chemistry. They have a series of special properties. The following is a summary of their special properties:

Solubility: Inorganic compounds vary in solubility. Some are easily soluble, some are soluble, some are difficult to dissolve, and some are insoluble. But generally speaking, inorganic compounds have greater solubility than organic compounds. At the same time, some inorganic compounds are soluble in water but insoluble in organic solvents, which is different from the solubility characteristics of organic compounds.
Heat resistance: Most inorganic compounds are heat-resistant and generally have a high melting point. In contrast, most organic compounds are not heat-resistant and have a low melting point. This feature makes inorganic compounds have better stability in high-temperature environments.
Flammability: Most inorganic compounds are non-combustible or have a high ignition point. Most organic compounds can burn. This feature makes inorganic compounds have a wide range of application values in fire prevention, flame retardancy, and other fields.
Chemical reaction: The chemical reaction of inorganic substances is generally simpler, with fewer side reactions and faster reaction speed. In contrast, the chemical reaction of organic substances is usually complex and has many side reactions, and the reaction speed is slower. This makes inorganic compounds easier to control and operate during chemical reactions.
Color and state: The color and state of inorganic compounds vary. For example, some inorganic substances present different colors such as light yellow, bright red, brick red, reddish brown, black, etc.; at room temperature, some inorganic substances are gases (such as hydrogen, nitrogen, etc.), some are liquids (such as water, hydrogen peroxide, etc.), and some are solids (such as sulfur, iodine, etc.). These changes in color and state provide an important basis for the identification and application of inorganic compounds.
Toxicity: Some inorganic compounds are toxic, such as fluorine, chlorine, bromine, iodine, and white phosphorus, and toxic gas compounds such as carbon monoxide, nitrogen dioxide, sulfur dioxide, and hydrogen sulfide. These toxic substances require special attention to safety protection during production and use.
In addition, inorganic compounds also have many other special properties, such as catalytic properties, optical properties, electrical properties, magnetic properties, etc. These properties make inorganic compounds have broad application prospects in the fields of catalysis, optical materials, electronic devices, magnetic materials, etc.

In summary, inorganic compounds have a series of special properties, which make inorganic compounds have wide application value in various fields. At the same time, it is also necessary to pay attention to the safety and environmental protection of inorganic compounds and comply with relevant regulations and standards during use.