You will need to refer to a periodic table for proton values. In this notation, the atomic number is not included. Symbol-mass format for the above atom would be written as Cr-52. For an example of this notation, look to the chromium atom shown below:Īnother way to refer to a specific atom is to write the mass number of the atom after the name, separated by a hyphen. The metals consist of the alkali metals, alkaline earths, transition metals, lanthanides, and actinides.Elements that are not metals include the metalloids, nonmetals, halogens, and noble gases. They are grouped together in the middle to the left-hand side of the periodic table. The "A" value is written as a superscript while the "Z" value is written as a subscript. Most elements on the periodic table are metals. Both the atomic number and mass are written to the left of the chemical symbol. It is a soft, ductile transition metal which. In tests, normally, a periodic table will be provided. Niobium is a chemical element with atomic number 41 and is represented with the symbol Nb in the Periodic Table. You can find a periodic table online or in a chemistry book. Other elemental information includes atomic weight and atomic number. It is color-coded and assigns each element a unique 1 or 2-letter abbreviation. The composition of any atom can be illustrated with a shorthand notation called A/Z format. The periodic table is a chart that organizes elements by their atomic structure. No negative environmental effects have been reported.\nonumber \] In laboratory animals, inhalation of niobium nitride and/or pentoxide leads to scarring of the lungs at exposure levels of 40 mg/m 3. It interferes with calcium as an activator of enzyme systems. Niobium, when inhaled, is retained mainly in the lungs, and secondarily in bones. Apart from measuring its concentration, no research on niobium in humans has been undertaken. Niobium and its compounds may be toxic (niobium dust causes eye and skin irritation), but there are no reports of human being poisoned by it. The amount of unmined reserves is not known, but there are extensive deposits of pytochlore. World production is around 25.000 tonnes per year. The main mining areas are Brazil, which produce more than 85% on the world's niobium, Zaire, Russia, Nigeria and Canada. Another mined metal is pyrochlore and this is now the most important. By convention, elements are organized in the periodic table, a structure that captures important patterns in their behavior.Devised by Russian chemist Dmitri Mendeleev (18341907) in 1869, the table places elements into columnsgroupsand rowsperiodsthat share certain properties. Niobium was mined chifely as columbite, and is formerly known as colombium (Cb). ![]() However, plant growing near niobium deposits can accumulate the metal to levels above 1 ppm. Plants generally show only traces of niobium and many have none at all, although some mosses and lichens can contain 0.45 ppm. Niobium alloys are used in surgical implants because they do not react with human tissue. Niobium is also used its pure form to make superconducting accelerating structures for particle accelerators. Niobium- tin and niobium- titanium alloys are used as wires for superconducting magnets capable of producing exceedingly strong magnetic fields. It is used in stainless steel alloys for nuclear reactors, jets, missiles, cutting tools, pipelines, super magnets and welding rods. Niobium carbide is used in cutting tools. Small amounts of niobium impart greater strenght to other metals, especially those that are exposed to low temperatures. ![]() It has a body-centered cubic crystalline structure and in its physical and chemical properties it. Niobium is used for the production of high-temperature-resistant alloys and special stainless steels. Niobium is a rare, soft, malleable, ductile, gray-white metal. The metal is inert to acids, even to aqua regia at room temperatures, but is attacked by hot, concentrated acids, and expecially by alkalis and oxidizing agents. It must be placed in a protective atmosphere when processed at even moderate temperatures because it tends to react with oxygen, carbon, the halogens, nitrogen, and sulfur. It has a body-centered cubic crystalline structure and in its physical and chemical properties it resembles tantalum. Niobium is a rare, soft, malleable, ductile, gray-white metal. ![]() Niobium - Nb Chemical properties of niobium - Health effects of niobium - Environmental effects of niobium
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