Phenylselenyl Bromide

See more Selenium products. Selenium (atomic symbol: Se, atomic number: 34) is a Block P, Group 16, Period 4 element with an atomic radius of 78.96. The number of electrons in each of Selenium's shells is 2, 8, 18, 6 and its electron configuration is [Ar] 3d¹⁰ 4s² 4p⁴. The selenium atom has a radius of 120 pm and a Van der Waals radius of 190 pm. Selenium is a non-metal with several allotropes: a black, vitreous form with an irregular crystal structure three red-colored forms with monoclinic crystal structures and a gray form with a hexagonal crystal structure, the most stable and dense form of the element. One of the most common uses for selenium is in glass production the red tint that it lends to glass neutralizes green or yellow tints from impurities in the glass materials. Selenium was discovered and first isolated by Jöns Jakob Berzelius and Johann Gottlieb Gahn in 1817. The origin of the name Selenium comes from the Greek word "Selênê," meaning moon.

See more Bromine products. Bromine (atomic symbol: Br, atomic number: 35) is a Block P, Group 17, Period 4 element. Its electron configuration is [Ar]4s²3d¹⁰4p⁵. The bromine atom has a radius of 102 pm and its Van der Waals radius is 183 pm. In its elemental form, bromine has a red-brown appearance. Bromine does not occur by itself in nature; it is found as colorless soluble crystalline mineral halide salts. Bromine was discovered and first isolated by Antoine Jérôme Balard and Leopold Gmelin in 1825-1826.