Element name: cadmium
Element symbol: Cd
English name of the element:
Element type: metal element
Relative atomic mass: 1 12.4
Atomic number: 48
Number of protons: 48
Neutron number:
Isotopes:
Molar mass: 1 12
Atomic radius:
Period: 5
Number of families: IIB
Electron layer arrangement: 2-8- 18- 18-2.
Ordinary valence:
Elemental substance:
Chemical symbols of elements:
Color and status:
Density:
Melting point:
Boiling point:
Discoverer: Luo Mai. Discovery date: 18 17.
Discovery process: 18 17, Luo Mai, Germany. Brown powder was separated from impure zinc oxide and heated with charcoal to make cadmium.
Element description: silvery white or leaden gray lustrous soft metal, malleable, density: 8.642g/cm3. Melting point: 320.9℃. The boiling point is 765℃. The valence is +2. The ionization energy is 8.993 electron volts. There are eight natural stable isotopes and eleven unstable artificial radioactive isotopes. It quickly loses its luster in the air and is covered with an oxide film to prevent further oxidation. Insoluble in water, soluble in most acids. Cadmium is +2 in all stable compounds, and its ions are colorless. Cadmium can form complex ions Cd(NH3)42+, Cd(CN)42- and CdI42-.
Source of elements: it mainly exists in the form of cadmium sulfide in nature; There is also a small amount of zinc ore, so it is also a by-product of zinc ore smelting.
Application of components: used for electric bottom, alloy manufacturing, etc. It can be made into neutron absorption rods in atomic reactors. Cadmium has a high oxidation potential, so it can be used as a protective film for iron, steel and copper, and is widely used as a stabilizer for electroplating, rechargeable batteries, TV picture tubes, yellow pigments and plastics. Cadmium compounds can be used to make pesticides, fungicides, pigments and paints.
Auxiliary data of elements: Compared with its similar elements of mercury and zinc, cadmium was discovered much later. Its content in the earth's crust is more than that of mercury, but once mercury appears, it attracts people's attention with its strong metallic luster, large proportion, special fluidity and ability to dissolve various metals. The content of cadmium in the earth's crust is much less than that of zinc, and it is often contained in a small amount of zinc ore and rarely mineralized alone. Metal cadmium is more volatile than zinc, so when zinc is smelted at high temperature, it escapes earlier than zinc and cannot escape human consciousness. This doomed that cadmium could not be found before zinc.
Biotoxicity: Cadmium will irritate respiratory tract, and long-term exposure will cause loss of sense of smell, and yellow spots or gradually yellow circles will appear on gums. Cadmium compounds are not easily absorbed by intestine, but can be absorbed by human body through breathing, and accumulate in liver or kidney, causing harm.
Cadmium was first discovered by Strommel, a professor of chemistry and medicine at the University of G? ttingen in Germany. He was also entrusted by the government as a drug dealer inspector. It was during his inspection of drug dealers that he observed problems in zinc-containing drugs, which prompted him to find cadmium in 18 17. Because the new metal found exists in zinc, it is named cadmium after the zinc-bearing ore smithsonite, and the element symbol is Cd.
Cadmium plum: ancient cooker, three-legged hollow. Originally made of pottery, it was also made of bronze in Shang and Zhou Dynasties. After the pot.
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Liupanshui bioengineering co., ltd. sells it, but it doesn't seem to be sold to individuals.