Table 20.5 The Group 17 elements nce connguration: ns Molar Melting Boiling Density mass, point, point, g cm ame Symbol g /m at25°C Normal form* 9 fluorine F 19.00 -220 188 151 almost colorless gas(O,) 17 chlorine Cl 35.45 101 34 1.66′ yellow-green gas 35 bromine Br 7991 59 3.12 red-brown liquid 33 iodine 126.90 114 184 4.95 purple-black nonmetallic solid 85 astatine At 210 300 350. nonmetallic solid Normal form means the appearance and state of the element at 25C and 1 atm. For the liquid at its boiling point Radioactive
4.0 3.2 3.0 2.7 电负性 FCl Br I
电负性
114 64 196 181 133 F 原子和离子半径
原子和离子半径
元素的性质(F,CD F2,最强的氧化剂,E=+287V,电解(KF+HF,75°C) UF6( volatile solid, processing核燃料; Fluorinated hydrocarbons, Teflon, they are inert..(聚四氟乙烯,塑 料王,稳定、耐腐) 大多数氟化物溶解性低(除AgF),尽管其丰度比C。 Cl2,电解NaCI( pale yellow- green gas) It reacts directly with nearly all the elements(C,N O, noble gases).强的氧化剂,氧化金属到高氧化态, 如: 2Fe(s)+3Cl2-2FeCl3(S →塑料,溶剂,杀虫剂;漂白纸,纺织品;水消毒
元素的性质 (F, Cl) • F2 , 最强的氧化剂,Eo = +2.87 V, 电解(KF+HF,75°C) UF6 (volatile solid), processing 核燃料;Fluorinated hydrocarbons, Teflon, they are inert.(聚四氟乙烯,塑 料王,稳定、耐腐) 大多数氟化物溶解性低(除AgF),尽管其丰度比Cl大。 • Cl2, 电解NaCl (pale yellow-green gas) It reacts directly with nearly all the elements (除C,N, O, noble gases ). 强的氧化剂, 氧化金属到高氧化态, 如: 2Fe(s) + 3Cl2 → 2FeCl3 (s) → 塑料,溶剂,杀虫剂; 漂白纸,纺织品;水消毒
电解池 2NaCl(aq+2H,2O()=2NaOH(aq+CI(8)+H(8) HF inlet Membrane H, outlet F, outlet H, outlet Brine 35% feed NaoH(aq Dilute HF/KF electrolyte NaoH(aq) brine Na Steel Carbon Anode(+ Cathode(-) cathode anode (+) 阴极 阳极 阳极 阴极 还原H到氧化F到F2 氧化C到(2还原H2O到H2
阳极 氧化F-到F2 阴极 还原H+到 H2 阳极 氧化Cl-到Cl2 阴极 还原H2O到H2 2NaCl(aq)+2H2O(l)=2NaOH(aq)+Cl2 (g)+H2 (g) 电解池