RENIO (Re) • Elemento 75 • Proprietà fisiche/Proprietà chimiche • Descrizione • Usi / Funzione • isotopi • Termochimica • reazioni • Electron Configurazione e Bonding

Discovery of rhenium is generally attributed to Noddack, Tacke, and Berg, who announced in 1925 they had detected the element in platinum oresand columbite. They also found the element in gadolinite and molybdenite. By working up 660 kg of molybdenite they were able in 1928 to extract1 g of rhenium. The price in 1928 was $10,000/g. Rhenium does not occur free in nature or as a compound in a distinct mineral species. It is, however,widely spread throughout the earth’s crust to the extent of about 0.001 ppm. Commercial rhenium in the U.S. today is obtained from molybdeniteroaster-flue dusts obtained from copper-sulfide ores mined in the vicinity of Miami, Arizona, and elsewhere in Arizona and Utah. Some molybdenitescontain from 0.002 to 0.2% rhenium. More than 150,000 troy ounces of rhenium are now being produced yearly in the United States. The total estimatedFree World reserve of rhenium metal is 3500 tons. Natural rhenium is a mixture of two isotopes, one of which has a very long half-life. Thirty nineother unstable isotopes are recognized. Rhenium metal is prepared by reducing ammonium perrhenate with hydrogen at elevated temperatures. Theelement is silvery white with a metallic luster; its density is exceeded only by that of platinum, iridium, and osmium, and its melting point is exceededonly by that of tungsten and carbon. It has other useful properties. The usual commercial form of the element is a powder, but it can be consolidatedby pressing and resistance-sintering in a vacuum or hydrogen atmosphere. This produces a compact shape in excess of 90% of the density of the metal.Annealed rhenium is very ductile, and can be bent, coiled, or rolled. Rhenium is used as an additive to tungsten and molybdenum-based alloys to impartuseful properties. It is widely used for filaments for mass spectrographs and ion gages. Rhenium-molybdenum alloys are superconductive at 10 K.Rhenium is also used as an electrical contact material as it has good wear resistance and withstands arc corrosion. Thermocouples made of Re-W areused for measuring temperatures up to 2200°C, and rhenium wire has been used in photoflash lamps for photography. Rhenium catalysts areexceptionally resistant to poisoning from nitrogen, sulfur, and phosphorus, and are used for hydrogenation of fine chemicals, hydrocracking, reforming,and disproportionation of olefins. Rhenium costs about $12/g (99.99% pure). Little is known of its toxicity; therefore, it should be handled with careuntil more data are available. 1

Proprietà fisiche

Punto di fusione:2* 3186 °C = 3459.15 K = 5766.8 °F
Punto di ebollizione:2* 5596 °C = 5869.15 K = 10104.8 °F
sublimazione Point:2
Triple Point:2
Punto critico:2
Densità:3 20.8 g/cm3

* - at 1 atm

configurazione elettronica

configurazione elettronica: [Xe] 6s2 4f14 5d5
Bloccare: d
Più alto livello di energia Occupato: 6
Elettroni di valenza:

numeri quantici:

n = 5
ℓ = 2
mℓ = 2
ms = +½

bonding

elettronegatività (scala Pauling):4 1.9
Electropositivity (scala Pauling): 2.1
Affinità elettronica:5 0.15 eV
ossidazione Uniti: +7,4,6
Funzione di lavoro:6 4.95 eV = 7.9299E-19 J

potenziale di ionizzazione

eV 7

kJ/mol

potenziale di ionizzazione

eV 7

kJ/mol

potenziale di ionizzazione	eV 7	kJ/mol
1	7.8335	755.8

Termochimica

Calore specifico: 0.137 J/g°C 8 = 25.510 J/mol°C = 0.033 cal/g°C = 6.097 cal/mol°C
Conduttività termica: 47.9 (W/m)/K, 27°C 9
Calore di fusione: 33.2 kJ/mol 10 = 178.3 J/g
Calore di vaporizzazione: 715 kJ/mol 11 = 3839.8 J/g

Stato della materia Entalpia di formazione (ΔHf°)12 entropia (S°)12 Energia libera di Gibbs (ΔGf°)12

(kcal/mol) (kJ/mol) (cal/K) (J/K) (kcal/mol) (kJ/mol)

(s) 0 0 8.81 36.86104 0 0

(g) 184.0 769.856 45.131 188.828104 173.2 724.6688

isotopi

nuclide Massa 13 Metà vita 13 spin nucleare 13 Energia di legame

160Re 159.98212(43)# 860(120) μs [0.82(+15-9) ms] (2-) 1,251.36 MeV
161Re 160.97759(22) 0.37(4) ms 1/2+ 1,268.75 MeV
162Re 161.97600(22)# 107(13) ms (2-) 1,276.82 MeV
163Re 162.972081(21) 390(70) ms (1/2+) 1,284.89 MeV
164Re 163.97032(17)# 0.53(23) s high 1,292.96 MeV
165Re 164.967089(30) 1# s 1/2+# 1,310.35 MeV
166Re 165.96581(9)# 2# s 2-# 1,318.42 MeV
167Re 166.96260(6)# 3.4(4) s 9/2-# 1,326.49 MeV
168Re 167.96157(3) 4.4(1) s (5+,6+,7+) 1,334.56 MeV
169Re 168.95879(3) 8.1(5) s 9/2-# 1,351.95 MeV
170Re 169.958220(28) 9.2(2) s (5+) 1,360.02 MeV
171Re 170.95572(3) 15.2(4) s (9/2-) 1,368.09 MeV
172Re 171.95542(6) 15(3) s -5 1,376.16 MeV
173Re 172.95324(3) 1.98(26) min (5/2-) 1,384.23 MeV
174Re 173.95312(3) 2.40(4) min 1,392.31 MeV
175Re 174.95138(3) 5.89(5) min (5/2-) 1,400.38 MeV
176Re 175.95162(3) 5.3(3) min 3+ 1,408.45 MeV
177Re 176.95033(3) 14(1) min 5/2- 1,416.52 MeV
178Re 177.95099(3) 13.2(2) min (3+) 1,424.59 MeV
179Re 178.949988(26) 19.5(1) min (5/2)+ 1,441.98 MeV
180Re 179.950789(23) 2.44(6) min (1)- 1,440.73 MeV
181Re 180.950068(14) 19.9(7) h 5/2+ 1,448.80 MeV
182Re 181.95121(11) 64.0(5) h 7+ 1,456.88 MeV
183Re 182.950820(9) 70.0(14) d 5/2+ 1,464.95 MeV
184Re 183.952521(5) 38.0(5) d 3(-) 1,473.02 MeV
185Re 184.9529550(13) STABILE 5/2+ 1,481.09 MeV
186Re 185.9549861(13) 3.7186(5) d 1- 1,489.16 MeV
187Re 186.9557531(15) 41.2(2)E+9 a 5/2+ 1,497.23 MeV
188Re 187.9581144(15) 17.0040(22) h 1- 1,505.30 MeV
189Re 188.959229(9) 24.3(4) h 5/2+ 1,513.38 MeV
190Re 189.96182(16) 3.1(3) min (2)- 1,512.13 MeV
191Re 190.963125(11) 9.8(5) min (3/2+,1/2+) 1,520.20 MeV
192Re 191.96596(21)# 16(1) s 1,528.27 MeV
193Re 192.96747(21)# 30# s [>300 ns] 5/2+# 1,536.35 MeV
194Re 193.97042(32)# 2# s [>300 ns] 1,535.10 MeV
I valori assegnati # non sono puramente derivati da dati sperimentali, ma almeno parzialmente da tendenze sistematiche. Gira con argomenti di assegnazione deboli sono racchiusi tra parentesi. 13

Abbondanza

Terra - composti di origine: oxides 14
Terra - L'acqua di mare: 0.000004 mg/L 15
Terra - Crosta: 0.0007 mg/kg = 0.00000007% 15
Terra - Totale: 60 ppb 16
Pianeta Mercurio) - Totale: 46 ppb 16
Venere - Totale: 64 ppb 16
condriti - Totale: 0.046 (relative to 106 atoms of Si) 17

Composti

Informazioni sulla sicurezza

Scheda di sicurezza - ACI Alloys, Inc.

Per maggiori informazioni

Link esterno:

fonti

(1) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; p 4:25-4:26.
(2) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; p 4:132.
(3) - Lide, David R. CRC Handbook of Chemistry and Physics, 84th ed.; CRC Press: Boca Raton, FL, 2002; p 4:39-4:96.
(4) - Dean, John A. Lange's Handbook of Chemistry, 11th ed.; McGraw-Hill Book Company: New York, NY, 1973; p 4:8-4:149.
(5) - Lide, David R. CRC Handbook of Chemistry and Physics, 84th ed.; CRC Press: Boca Raton, FL, 2002; p 10:147-10:148.
(6) - Speight, James. Lange's Handbook of Chemistry, 16th ed.; McGraw-Hill Professional: Boston, MA, 2004; p 1:132.
(7) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; p 10:178 - 10:180.
(8) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; p 4:133.
(9) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; pp 6:193, 12:219-220.
(10) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; pp 6:123-6:137.
(11) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; pp 6:107-6:122.
(12) - Dean, John A. Lange's Handbook of Chemistry, 12th ed.; McGraw-Hill Book Company: New York, NY, 1979; p 9:4-9:94.
(13) - Atomic Mass Data Center. http://amdc.in2p3.fr/web/nubase_en.html (accessed July 14, 2009).
(14) - Silberberg, Martin S. Chemistry: The Molecular Nature of Matter and Change, 4th ed.; McGraw-Hill Higher Education: Boston, MA, 2006, p 965.
(15) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; p 14:17.
(16) - Morgan, John W. and Anders, Edward, Proc. Natl. Acad. Sci. USA 77, 6973-6977 (1980)
(17) - Brownlow, Arthur. Geochemistry; Prentice-Hall, Inc.: Englewood Cliffs, NJ, 1979, pp 15-16.

RENIO

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Descrizione • Usi / Funzione