Chlorine reacts with iron.

The reaction between chlorine and iron is violent combustion, which releases a lot of heat and brownish red or brownish yellow smoke. After adding water, the solution is brown.

First, the meaning of iron and chlorine.

Iron is a chemical element, not a crystal. Its chemical symbol is Fe and its atomic number is 26. It is located in the eighth group of the fourth period of the periodic table of chemical elements and is the representative of iron group elements. It is a transition metal and the second most abundant metal element in the earth's crust. Iron is a lively and strong reducing agent with valence of 0, +2, +3 and +6, and the most common valence states are +2 and +3.

Chlorine gas, chemical formula Cl? . It is yellow-green at normal temperature and pressure, and has a strong pungent smell. It is denser than air, easily soluble in water, easily compressed and liquefied into golden liquid chlorine. It is one of the main products in chlor-alkali industry and can be used as a strong oxidant. When chlorine gas is mixed with hydrogen with a volume fraction greater than 5%, it may explode in case of strong light. Chlorine gas can react with organic and inorganic substances to produce various chlorides.

Second, the application of chlorine.

1. Chemical industry is used to produce inorganic chemical products, such as sodium hypochlorite, aluminum trichloride, ferric trichloride, bleaching powder, bromine, phosphorus trichloride, etc. It is also used to produce organic chlorides, such as chloroacetic acid, epichlorohydrin and monochlorobenzene. It is also used to produce neoprene, plastics and plasticizers. Daily chemical industry is used to produce synthetic detergent raw materials such as sodium alkyl sulfonate and sodium alkyl benzene sulfonate.

2. In the electronics industry, high-purity chlorine gas is mainly used for dry etching, optical fiber, crystal growth and thermal oxidation in the electronics industry.

3. Used for sewage treatment of brewery. China patent discloses the method of treating beer wastewater with chlorine. Chlorine is widely used in water supply companies because of its low price, low dosage, reliable disinfection and mature technology. Chlorine can also deodorize and remove microorganisms, and the removal rate of biological oxygen consumption and chemical oxygen consumption is also high, which can ensure the stability of recycled water quality, so it is more suitable for brewery sewage treatment.