1/31/2024 0 Comments Powdered antimonySpecific heat capacity: 519 J kg -1 K -1. The only neutral compound of argon is argon fluorohydride, HArF, but the compound collapses at very low temperature.įirst "noble" gas, discovered by William Ramsay in 1894.Ītomic number: 18, Relative atomic mass: 39.948, RD 1.40 (87 K), MP= -189 oC, BP = -186 oC. Most abundant noble gas, 0.9% of atmosphere by volume. With other substances), in compressed air cylinders, non-metal, inert,Ĭolourless, odourless, noble gas at room temperature and pressure, 0.93% of the air, extracted from liquid air.Ĭhemically inactive, no compounds, monatomic gaseous element, in incandescent light bulbs, fluorescent tubes, lasers, and welding. ![]() See: Argon Elements, Compounds, (Commercial).Īrgon, Ar (Greek argos idle, because this noble gas will not react Specific heat capacity: 210 J kg -1 K -1. Yellow antimony lead paint is said to have been used on Nebuchadnezzar'sĪtomic number: 51, Relative atomic mass: 121.75, RD 6.68, MP = 630.5 oC, Naples yellow, antimony white and antimony black are all highly toxic cumulative poisons. It was in the black powder eye makeup, kohl, as used by Jezebel in the Bible (2 Kings 9: 30). It was used in emetic medicine, but is toxic in excess. To produce neutrons, from stibnite Sb 2S 3.Īntimony black (powdered antimony used to give plaster casts metallic look).Īntimony and antimony salts are available from artists' suppliers. It burns in air, but has no reaction with water or dilute acids, attachedīy halogens and oxidizing acids, poor conductor of heat andĮlectricity, used in alloys for cable covers, pewter and lead cell accumulator plates, donor impurity in silicon chips, radioactive isotopes (grey wolf), hence the name "anti monos" (against singleness), because it has two forms. With a gleaming surface (star antimony) or as a grey powder, Powder, shot, particles, in plastics, textiles, rubber, adhesives, pigments,Īlloys in solder, sheet, pipe, bearing and type, blue white silvery metal Antimony pentoxide is manufactured by both Philadelphia Quartz and Laurel Industries under the Nyacol and Fireshield trade names.Properties of elements, Actinium to ZirconiumĪmericium, Am ( America) ("amer-ee-sium"), radioactive actinide,Īm 241 isotope in nuclear waste, used in smoke detectors,īecause Americium ionizes atoms of air producing highly ionizing alpha particles.Īntimony, Sb (Greek anti monos not alone) (Latin stibium, hence "Sb"), stibium, antimony regulus, silver-white, brittle metalloid, However, because it is more efficient than the trioxide, the pentoxide is at least cost-equivalent. This can result in color formation and a lower flame-retarding efficiency of the system.Īntimony pentoxide is priced about two to three times higher than the trioxide. ![]() Stabilizers used to prevent the particles from growing are caustic, and can react with the halogen in the formulation. Powdered antimony pentoxide is used primarily in plastics. The submicrometer antimony pentoxide is also more evenly dispersed in the fiber, resulting in better physical properties. The antimony in this form can easily pass through the spinnerets without clogging the openings, whereas standard grades of antimony trioxide would rapidly clog the openings and necessitate frequent shutdowns for cleaning. It can be added to the molten or dissolved polymer prior to forming the fiber. Submicrometer antimony pentoxide is primarily used to impart flame retardancy to fibers and fabrics. Properties of this unique flame retardant synergist are listed in Table. It is insoluble in water, but soluble in hot concentrated acids. Antimony pentoxide is available as a nonpigmenting colloidal suspension in either water or organic media or as an agglomerated powder. The second most widely used antimony synergist is antimony pentoxide, Sb 2O 5, produced by the oxidation of the trioxide using either a peroxide or nitric acid. The decomposition products, water and char, cool the flame reactions while slowing the production and volatilization of flammable decomposition products. When the treated fabric is exposed to a flame, the oxide reacts with the hydroxyl groups of the cellulose (qv) causing them to decompose endothermically. ![]() It can be applied by impregnating a fabric with a soluble antimony salt followed by a second treatment that precipitates antimony oxide in the fibers. Antimony Oxide as a Primary Flame RetardantĪntimony oxide behaves as a condensed-phase flame retardant in cellulosic materials.
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