Cadmium (ge, sound barrier), CADMIUM, derived from kadmia, meaning "earth", discovered in 1817. Found in nature with zinc. It is an excellent metal that absorbs neutrons and can be used in rods to slow nuclear chain reactions in atomic reactors and is useful in zinc-cadmium batteries. Cadmium yellow pigment, made from its vivid sulfides, is popular among artists.
Element Name: Cadmium
Element Symbol: Cd
English Element Name:
Type element: Metallic element
Relative atomic mass: 112.4
Atomic number: 48
Number of protons: 48
Number of neutrons:
Isotopes:
Molar mass: 112
Atomic radius:
Half-life: 5
Group: IIB
Electronic shell arrangement: 2-8-18-18-2
Common valence:
Elementary substance:
Elementary chemical symbol:
Color and state:
Density:
Melting point:
Boiling point:
Discovered by: Stromeier Year of discovery: 1817
Discovery process: In 1817, Stromeier in Germany separated brown powder from impure zinc oxide and heated it with charcoal to obtain cadmium.
Description of the element: Shiny silvery white or lead gray soft metal, ductile, density: 8.642 g/cm3. Melting point: 320.9℃. Boiling point 765℃. The valence is +2. Ionization energy 8.993 electron volts. There are eight natural stable isotopes and eleven artificial radioactive isotopes that are unstable. It quickly loses its shine in the air and becomes covered with an oxide film to prevent further oxidation. Insoluble in water, soluble in most acids. Cadmium has a valency of +2 in all stable compounds and its ions are colorless. Cadmium can form complex ions Cd(NH3)42+, Cd(CN)42- and CdI42-.
Element source: exists mainement as cadmium sulfide ore in nature; it also exists in small amounts in zinc ore, so it is also a byproduct of zinc ore smelting.
Element Uses: Used in electrode bases, alloy manufacturing, etc. ; and can be made into neutron-absorbing rods in atomic reactors. Cadmium has a high oxidation potential, so it can be used as a protective film for iron, steel and copper. It is widely used in electroplating and is used in rechargeable batteries, television cathode ray tubes, high-quality pigments and as an agent. stabilizer for plastics. Cadmium compounds can be used in the manufacture of pesticides, fungicides, pigments, paints, etc.
Auxiliary information about the element: Compared to its congeners mercury and zinc, cadmium was discovered much later. It is Pmore abundant in the earth's crust than mercury, but once mercury appeared, it attracted people's attention with its strong metallic luster, high density, special fluidity, and ability to dissolve a variety of metals. Cadmium in the earth's crust is much lower than that of zinc. It is often present in small quantities in zinc ores and is rarely mined alone. Metallic cadmium is more volatile than zinc, so when zinc is melted at high temperatures, it escapes earlier than zinc, thus escaping people's consciousness. It is doomed that cadmium cannot be discovered before zinc.
Biological toxicity: Cadmium can cause respiratory tract irritation. Long-term exposure may cause anosmia, yellow spots on the gums or yellow circles are not easily absorbed by the intestines, but can be absorbed into the intestines.estins. body through respiration and accumulates. Causes liver or kidney damage.
The first person to discover cadmium was Strohmeier, professor of chemistry and medicine at the University of Göttingen in Germany. He is also a government-appointed drug trafficker inspection commissioner. It was during his inspection of drug dealers that he noticed problems in medicines containing zinc that led him to discover cadmium in 1817. Since the newly discovered metal existed in zinc, it was named Cadmium after the name of the zinc-containing ore Calamine, and the element symbol was defined as Cd.
Also cadmium lì: ancient kitchen utensils with three hollow cores. Initially made in pottery, bronze was also used during the Shang and Zhou dynasties. Later it usually refers to pot.
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Available from Liupanshui Bioengineering Co., Ltd. , but it does not appear to be available for personal sale