Niobium or columbium is the chemical element with the symbol Nb and the atomic number 4. Physical and chemical properties Niobium. Niobium is in many ways similar to its predecessors in group 5. Application of the given chemical element in the industry.
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A rare, soft, grey, ductile transition metal, niobium is found in the minerals pyrochlore, the main commercial source for niobium, and columbite. In 1864 and 1865, a series of scientific findings clarified that niobium and columbium were the same element (as distinguished from tantalum), and for a century both names were used interchangeably. Both tantalum and niobium react with chlorine and traces of oxygen, including atmospheric concentrations, with niobium forming two compounds: the white volatile niobium pentachloride (NBCL5) and the non-volatile niobium oxychloride (NBOCL3). Although de Marignac was able to produce tantalum-free niobium on an increased scale by 1866, it was not until the early 20th century that niobium was first used commercially, in incandescent lamp filaments. Columbium (symbol Cb) was the name originally given to this element by Hatchett, and this name remained in use in American journals-the last paper published by American Chemical Society with columbium in its title dates from 1953-while niobium was used in Europe.