ITÉRBIO

Introdução

Número atômico: 70
Grupo: Nenhum
Peso atômico: 173.04
Período: 6
Número CAS: 7440-64-4

Classificação

Calcogênio
halogênio
Gás nobre
Lantanóides
Actinóide
Terra-rara
Platinum Metal Group
Transuranium
Não Isótopos Estáveis
Sólido
Líquido
Gás
Sólido (previsto)

Descrição • Usos / Função

Marignac in 1878 discovered a new component, which he called ytterbia, in the earth then known as erbia. In 1907, Urbain separated ytterbia intotwo components, which he called neoytterbia and lutecia. The elements in these earths are now known as ytterbium and lutetium, respectively. Theseelements are identical with aldebaranium and cassiopeium, discovered independently and at about the same time by von Welsbach. Ytterbium occursalong with other rare earths in a number of rare minerals. It is commercially recovered principally from monazite sand, which contains about 0.03%.Ion-exchange and solvent extraction techniques developed in recent years have greatly simplified the separation of the rare earths from one another.The element was first prepared by Klemm and Bonner in 1937 by reducing ytterbium trichloride with potassium. Their metal was mixed, however,with KCl. Daane, Dennison, and Spedding prepared a much purer form in 1953 from which the chemical and physical properties of the element couldbe determined. Ytterbium has a bright silvery luster, is soft, malleable, and quite ductile. While the element is fairly stable, it should be kept in closedcontainers to protect it from air and moisture. Ytterbium is readily attacked and dissolved by dilute and concentrated mineral acids and reacts slowlywith water. Ytterbium has three allotropic forms with transformation points at –13° and 795°C. The beta form is a room-temperature, face-centered,cubic modification, while the high-temperature gamma form is a body-centered cubic form. Another body-centered cubic phase has recently beenfound to be stable at high pressures at room temperatures. The beta form ordinarily has metallic-type conductivity, but becomes a semiconductor whenthe pressure is increased above 16,000 atm. The electrical resistance increases tenfold as the pressure is increased to 39,000 atm and drops to about80% of its standard temperature-pressure resistivity at a pressure of 40,000 atm. Natural ytterbium is a mixture of seven stable isotopes. Twenty sixother unstable isotopes and isomers are known. Ytterbium metal has possible use in improving the grain refinement, strength, and other mechanicalproperties of stainless steel. One isotope is reported to have been used as a radiation source as a substitute for a portable X-ray machine where electricityis unavailable. Few other uses have been found. Ytterbium metal is commercially available with a purity of about 99.9% for about $5/g. Ytterbiumhas a low acute toxic rating, but may present a carcinogenic hazard. 1

Propriedades físicas

Ponto de fusão:2*  819 °C = 1092.15 K = 1506.2 °F
Ponto de ebulição:2* 1196 °C = 1469.15 K = 2184.8 °F
Ponto de sublimação:2 
Ponto Triplo:2 
Ponto crítico:2 
Densidade:3  6.90 g/cm3

* - at 1 atm

Configuração Electron

Configuração Electron:  *[Xe] 6s2 4f14
Quadra: f
Mais alto nível de energia Ocupado: 6
Elétrons de valência: 2

Números quânticos:

n = 4
ℓ = 3
m = 3
ms = -½

Colagem

Electron Affinity:4 -0.020 eV
oxidação Unidos: +3,2

potencial de ionização   eV 5  kJ/mol  
1 6.25416    603.4
potencial de ionização   eV 5  kJ/mol  
2 12.1761    1174.8
potencial de ionização   eV 5  kJ/mol  
3 25.05    2417.0
4 43.56    4202.9

Termoquímica

Calor específico: 0.155 J/g°C 6 = 26.821 J/mol°C = 0.037 cal/g°C = 6.410 cal/mol°C
Condutividade térmica: 34.9 (W/m)/K, 27°C 7
Calor de fusão: 7.66 kJ/mol 8 = 44.3 J/g
Calor da vaporização: 128.9 kJ/mol 9 = 744.9 J/g
Estado da matéria Entalpia de formação (ΔHf°)10 entropia (S°)10 Gibbs Energia Livre (ΔGf°)10
(kcal/mol) (kJ/mol) (cal/K) (J/K) (kcal/mol) (kJ/mol)
(s) 0 0 14.31 59.87304 0 0
(g) 36.4 152.2976 41.35 173.0084 28.3 118.4072

isótopos

nuclide Massa 11 Meia vida 11 spin nuclear 11 Energia de ligação
148Yb 147.96742(64)# 250# ms 0+ 1,177.05 MeV
149Yb 148.96404(54)# 0.7(2) s (1/2+,3/2+) 1,185.12 MeV
150Yb 149.95842(43)# 700# ms [>200 ns] 0+ 1,202.51 MeV
151Yb 150.95540(32) 1.6(5) s (1/2+) 1,210.58 MeV
152Yb 151.95029(22) 3.04(6) s 0+ 1,218.65 MeV
153Yb 152.94948(21)# 4.2(2) s 7/2-# 1,236.03 MeV
154Yb 153.946394(19) 0.409(2) s 0+ 1,244.11 MeV
155Yb 154.945782(18) 1.793(19) s (7/2-) 1,252.18 MeV
156Yb 155.942818(12) 26.1(7) s 0+ 1,260.25 MeV
157Yb 156.942628(11) 38.6(10) s 7/2- 1,268.32 MeV
158Yb 157.939866(9) 1.49(13) min 0+ 1,285.71 MeV
159Yb 158.94005(2) 1.67(9) min 5/2(-) 1,284.46 MeV
160Yb 159.937552(18) 4.8(2) min 0+ 1,301.85 MeV
161Yb 160.937902(17) 4.2(2) min 3/2- 1,309.92 MeV
162Yb 161.935768(17) 18.87(19) min 0+ 1,317.99 MeV
163Yb 162.936334(17) 11.05(25) min 3/2- 1,326.06 MeV
164Yb 163.934489(17) 75.8(17) min 0+ 1,334.13 MeV
165Yb 164.93528(3) 9.9(3) min 5/2- 1,342.21 MeV
166Yb 165.933882(9) 56.7(1) h 0+ 1,350.28 MeV
167Yb 166.934950(5) 17.5(2) min 5/2- 1,358.35 MeV
168Yb 167.933897(5) ESTÁVEL 0+ 1,366.42 MeV
169Yb 168.935190(5) 32.026(5) d 7/2+ 1,374.49 MeV
170Yb 169.9347618(26) ESTÁVEL 0+ 1,382.56 MeV
171Yb 170.9363258(26) ESTÁVEL 1/2- 1,390.63 MeV
172Yb 171.9363815(26) ESTÁVEL 0+ 1,398.70 MeV
173Yb 172.9382108(26) ESTÁVEL 5/2- 1,406.78 MeV
174Yb 173.9388621(26) ESTÁVEL 0+ 1,414.85 MeV
175Yb 174.9412765(26) 4.185(1) d 7/2- 1,413.60 MeV
176Yb 175.9425717(28) ESTÁVEL 0+ 1,421.68 MeV
177Yb 176.9452608(28) 1.911(3) h (9/2+) 1,429.75 MeV
178Yb 177.946647(11) 74(3) min 0+ 1,437.82 MeV
179Yb 178.95017(32)# 8.0(4) min (1/2-) 1,436.57 MeV
180Yb 179.95233(43)# 2.4(5) min 0+ 1,444.65 MeV
181Yb 180.95615(43)# 1# min 3/2-# 1,452.72 MeV
Os valores marcados # não são puramente derivado a partir de dados experimentais, mas, pelo menos, parcialmente a partir de tendências sistemáticas. Gira com argumentos de atribuição fracos estão entre parênteses. 11

Abundância

Terra - Os compostos de origem: phosphates 12
Terra - A água do mar: 0.00000082 mg/L 13
Terra -  crosta:  3.2 mg/kg = 0.00032% 13
Terra -  Total:  229 ppb 14
Planeta Mercúrio) -  Total:  176 ppb 14
Vênus -  Total:  240 ppb 14
condritos - Total: 0.18 (relative to 106 atoms of Si) 15

compostos

Informação de Segurança


Material Safety Data Sheet - ACI Alloys, Inc.

Para maiores informações

Links externos:

revistas:
(1) Folger, Tim. The Secret Ingredients of Everything. National Geographic, June 2011, pp 136-145.

Fontes

(1) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; p 4:35.
(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) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; p 10:178 - 10:180.
(7) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; p 4:133.
(8) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; pp 6:193, 12:219-220.
(9) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; pp 6:123-6:137.
(10) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; pp 6:107-6:122.
(11) - Dean, John A. Lange's Handbook of Chemistry, 12th ed.; McGraw-Hill Book Company: New York, NY, 1979; p 9:4-9:94.
(12) - Atomic Mass Data Center. http://amdc.in2p3.fr/web/nubase_en.html (accessed July 14, 2009).
(13) - Silberberg, Martin S. Chemistry: The Molecular Nature of Matter and Change, 4th ed.; McGraw-Hill Higher Education: Boston, MA, 2006, p 965.
(14) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; p 14:17.
(15) - Morgan, John W. and Anders, Edward, Proc. Natl. Acad. Sci. USA 77, 6973-6977 (1980)
(16) - Brownlow, Arthur. Geochemistry; Prentice-Hall, Inc.: Englewood Cliffs, NJ, 1979, pp 15-16.