Period 5 element with most production coming from the Xikuangshan Mine in Hunan. Antimony compounds are prominent additives for chlorine and bromine containing fire retardants found in many commercial and domestic products. The largest application for metallic antimony is as alloying material for lead and tin. It improves the properties of the alloys which are used as in solders, bullets and ball bearings. An emerging application is the use of antimony in microelectronics. Tellurium is a chemical element that has the symbol Te and atomic number 52. A brittle, mildly toxic, rare, silver-white metalloid which looks similar to tin, tellurium is chemically related
Systematic element name for 4). There are two elision rules designed to prevent odd-looking names. The suffix "-ium" overrides traditional chemical suffix rules; thus elements 117 and 118 were "ununseptium" and "ununoctium", not "ununseptine" and "ununocton". This does not apply to the final trivial names these elements receive once confirmed; thus element 117 and 118 are now "tennessine" and "oganesson". For these trivial names, all elements receive the suffix "-ium", except those in group 17 which receive "-ine" (like the halogens) and those in group 18 which receive "-on" (like the noble gases). The systematic symbol is formed by taking the first letter