Boron Boron Boron is a chemical element with symbol B and atomic number 5. Produced entirely by cosmic ray spallation and supernovae and not by stellar nucleosynthesis, it is a low-abundance element in the Solar system and in the Earth's crust. Boron is concentrated on Earth by the water-solubility of its more common naturally occurring compounds, the borate minerals. These are mined industrially as evaporites, such as borax and kernite. The largest known boron deposits are in Turkey, the largest producer of boron minerals. Elemental boron is a metalloid that is found in small amounts in meteoroids but chemically uncombined boron
Tellurium hexafluoride Tellurium hexafluoride Tellurium hexafluoride is a chemical compound of tellurium and fluorine with the chemical formula TeF. It is a colorless, highly toxic gas with an extremely unpleasant smell. Tellurium hexafluoride is most commonly prepared by passing fluorine gas over tellurium at 150 °C. Below this temperature a mixture of lower fluorides form, including tellurium tetrafluoride and ditellurium decafluoride. It can also be prepared by passing fluorine gas over TeO or indirectly by reacting TeO with SeF to produce TeF and then heating TeF in excess of 200 °C to make TeF and Te. Tellurium hexafluoride is a highly symmetric