SÓDIO

Introdução

Número atômico: 11
Grupo: 1 or I A
Peso atômico: 22.98977
Período: 3
Número CAS: 7440-23-5

Classificação

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

Descrição • Usos / Função

Long recognized in compounds, sodium was first isolated by Davy in 1807 by electrolysis of caustic soda. Sodium is present in fair abundance in the sun and stars. The D lines of sodium are among the most prominent in the solar spectrum. Sodium is the sixth most abundant element on earth, comprising about 2.6% of the earth’s crust; it is the most abundant of the alkali group of metals of which it is a member. The most common compound is sodium chloride, but it occurs in many other minerals, such as soda niter, cryolite, amphibole, zeolite, sodalite,etc. It is a very reactive element and is never found free in nature. It is now obtained commercially by the electrolysis of absolutely dry fused sodium chloride. This method is much cheaper than that of electrolyzing sodium hydroxide, as was used several years ago. Sodium is a soft, bright, silvery metal which floats on water, decomposing it with the evolution of hydrogen and the formation of the hydroxide. It may or may not ignite spontaneously on water, depending on the amount of oxide and metal exposed to the water. It normally does not ignite in air at temperatures below 115°C. Sodium should be handled with respect, as it can be dangerous when improperly handled. Metallic sodium is vital in the manufacture of sodamide and esters, and in the preparation of organic compounds. The metal may be used to improve the structure of certain alloys, to descale metal, to purify molten metals, and as a heat transfer agent. An alloy of sodium with potassium, NaK, is also an important heat transfer agent. Sodium compounds are important to the paper, glass, soap, textile, petroleum, chemical, and metal industries. Soap is generally a sodium salt of certain fatty acids. The importance of common salt to animal nutrition has been recognized since prehistoric times. Among the many compounds that are of the greatest industrial importance are common salt (NaCl), soda ash (Na2CO3), baking soda (NaHCO3), caustic soda (NaOH), Chile saltpeter (NaNO3), di- and tri-sodium phosphates, sodium thiosulfate (hypo, Na2S2O3 · 5H2O), and borax (Na2B4O7 · 10H2O). Seventeen isotopes of sodium are recognized. Metallic sodium is priced at about $250/kg (99.95%). On a volume basis, it is the cheapest of all metals. Sodium metal should be handled with great care. It should be kept in an inert atmosphere and contact with water and other substances with which sodium reacts should be avoided. 1

• "is still important in the manufacture of many chemicals, including pharmaceuticals and dyes such as indigo." 2
• "Sodium is used in making sodium peroxide, sodium cyanide, and in the manufacture of many complex compounds used as drugs and dyes. Its activity makes it valuable for the study of typical chemical actions. The alloy of sodium with mercury (sodium amalgam) is an important reducing agent. A sodium-lead alloy is used in making ethyl gasoline. Another use for sodium is in sodium vapor lamps used to light our highways with the bright yellow light which is characteristic of sodium. The sodium is vaporized and heated to incandescence by the electric current." 3
• "The metal itself is used as a reducing agent in the manufacture of drugs and dyes and in the metallurgy of such metals as titanium and zirconium...Highway lamps often incorporate Na arcs, which produce a bright yellow glow." 4
• "Sodium chloride, from which sodium is extracted by electrolysis, can be obtained in a fairly pure form by the evaporation of seawater in large ponds." 5

Propriedades físicas

Ponto de fusão:6*  97.80 °C = 370.95 K = 208.04 °F
Ponto de ebulição:6* 883 °C = 1156.15 K = 1621.4 °F
Ponto de sublimação:6 
Ponto Triplo:6 
Ponto crítico:6 2300 °C = 2573.15 K = 4172 °F 6
Densidade:7  0.97 g/cm3

* - at 1 atm

Configuração Electron

Configuração Electron: [Ne] 3s1
Quadra: s
Mais alto nível de energia Ocupado: 3
Elétrons de valência: 1

Números quânticos:

n = 3
ℓ = 0
m = 0
ms = +½

Colagem

Eletronegatividade (escala Pauling):8 0.93
Electropositivity (escala Pauling): 3.07
Electron Affinity:9 0.547926 eV
oxidação Unidos: +1
Função no trabalho:10 2.70 eV = 4.3254E-19 J

potencial de ionização   eV 11  kJ/mol  
1 5.13908    495.8
2 47.2864    4562.4
3 71.62    6910.3
potencial de ionização   eV 11  kJ/mol  
4 98.91    9543.4
5 138.4    13353.6
6 172.18    16612.8
7 208.5    20117.2
potencial de ionização   eV 11  kJ/mol  
8 264.25    25496.2
9 299.864    28932.5
10 1465.121    141362.7
11 1648.702    159075.5

Termoquímica

Calor específico: 1.228 J/g°C 12 = 28.231 J/mol°C = 0.293 cal/g°C = 6.747 cal/mol°C
Condutividade térmica: 141 (W/m)/K, 27°C 13
Calor de fusão: 2.598 kJ/mol 14 = 113.0 J/g
Calor da vaporização: 96.96 kJ/mol 15 = 4217.5 J/g
Estado da matéria Entalpia de formação (ΔHf°)16 entropia (S°)16 Gibbs Energia Livre (ΔGf°)16
(kcal/mol) (kJ/mol) (cal/K) (J/K) (kcal/mol) (kJ/mol)
(s) 0 0 12.30 51.4632 0 0
(ℓ) 0.575 2.4058 13.83 57.86472 0.119 0.497896
(g) 25.75 107.738 36.71 153.59464 18.48 77.32032

isótopos

nuclide Massa 17 Meia vida 17 spin nuclear 17 Energia de ligação
18Na 18.02597(5) 1.3(4)E-21 s (1-)# 113.39 MeV
19Na 19.013877(13) <40 ns (5/2+)# 132.64 MeV
20Na 20.007351(7) 447.9(23) ms 2+ 146.30 MeV
21Na 20.9976552(8) 22.49(4) s 3/2+ 163.69 MeV
22Na 21.9944364(4) 2.6027(10) yr 3+ 174.55 MeV
23Na 22.9897692809(29) ESTÁVEL 3/2+ 187.28 MeV
24Na 23.99096278(8) 14.9590(12) h 4+ 194.42 MeV
25Na 24.9899540(13) 59.1(6) s 5/2+ 203.42 MeV
26Na 25.992633(6) 1.077(5) s 3+ 208.70 MeV
27Na 26.994077(4) 301(6) ms 5/2+ 214.91 MeV
28Na 27.998938(14) 30.5(4) ms 1+ 219.25 MeV
29Na 29.002861(14) 44.9(12) ms 3/2(+#) 223.60 MeV
30Na 30.008976(27) 48.4(17) ms 2+ 226.08 MeV
31Na 31.01359(23) 17.0(4) ms (3/2+) 229.50 MeV
32Na 32.02047(38) 12.9(7) ms (3-,4-) 231.05 MeV
33Na 33.02672(94) 8.2(2) ms 3/2+# 233.53 MeV
34Na 34.03517(96)# 5.5(10) ms 1+ 233.22 MeV
35Na 35.04249(102)# 1.5(5) ms 3/2+# 234.77 MeV
36Na 36.05148(102)# <260 ns 234.46 MeV
37Na 37.05934(103)# 1# ms [>1.5 μs] 3/2+# 235.07 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. 17

reações

Abundância

Terra - Os compostos de origem: halide salts or brines 23
Terra - A água do mar: 10800 mg/L 24
Terra -  crosta:  0.000236 mg/kg = 0.0000000236% 24
Terra -  Manto:  0.8% 25
Terra -  litosfera:  2.27% 26
Terra -  Hidrosfera:  1.1% 26
Terra -  Total:  1250 ppm 27
Planeta Mercúrio) -  Total:  200 ppm 27
Vênus -  Total:  1390 ppm 27
condritos - Total: 4.6×104 (relative to 106 atoms of Si) 28
Corpo humano - Total: 0.14% 29

compostos

Informação de Segurança


Material Safety Data Sheet - ACI Alloys, Inc.

Para maiores informações

Links externos:

Fontes

(1) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; p 4:29.
(2) - Ebbing, Darrell D. General Chemistry 3rd ed.; Houghton Mifflin Company: Boston, MA, 1990; p 58.
(3) - Brownlee, Raymond B., Fuller, Robert W., and Whitsit, Jesse E. Elements of Chemistry; Allyn and Bacon: Boston, Massachusetts, 1959; p 180.
(4) - Whitten, Kenneth W., Davis, Raymond E., and Peck, M. Larry. General Chemistry 6th ed.; Saunders College Publishing: Orlando, FL, 2000; p 924.
(5) - Brady, James E. and Senese, Fred. Chemistry: Matter and Changes, 4th ed.; John Wiley and Sons: Hoboken, New Jersey, 2004; p 1012.
(6) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; p 4:132.
(7) - Lide, David R. CRC Handbook of Chemistry and Physics, 84th ed.; CRC Press: Boca Raton, FL, 2002; p 4:39-4:96.
(8) - Dean, John A. Lange's Handbook of Chemistry, 11th ed.; McGraw-Hill Book Company: New York, NY, 1973; p 4:8-4:149.
(9) - Lide, David R. CRC Handbook of Chemistry and Physics, 84th ed.; CRC Press: Boca Raton, FL, 2002; p 10:147-10:148.
(10) - Speight, James. Lange's Handbook of Chemistry, 16th ed.; McGraw-Hill Professional: Boston, MA, 2004; p 1:132.
(11) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; p 10:178 - 10:180.
(12) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; p 4:133.
(13) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; pp 6:193, 12:219-220.
(14) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; pp 6:123-6:137.
(15) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; pp 6:107-6:122.
(16) - Dean, John A. Lange's Handbook of Chemistry, 12th ed.; McGraw-Hill Book Company: New York, NY, 1979; p 9:4-9:94.
(17) - Atomic Mass Data Center. http://amdc.in2p3.fr/web/nubase_en.html (accessed July 14, 2009).
(18) - Ebbing, Darrell D. General Chemistry 3rd ed.; Houghton Mifflin Company: Boston, MA, 1990; p 71.
(19) - Ebbing, Darrell D. General Chemistry 3rd ed.; Houghton Mifflin Company: Boston, MA, 1990; pp 139, 195, 197.
(20) - Zumdahl, Steven and Zumdahl, Susan A. Chemistry 9th ed.; Brooks/Cole: Belmont, CA, 2014; p 131.
(21) - Swaddle, T.W. Inorganic Chemistry; Academic Press: San Diego, 1997; p 368.
(22) - Atkins, Jones, and Laverman. Chemical Principles 6th ed.; W.H. Freeman and Company: New York, NY, 2013; p F94.
(23) - Silberberg, Martin S. Chemistry: The Molecular Nature of Matter and Change, 4th ed.; McGraw-Hill Higher Education: Boston, MA, 2006, p 965.
(24) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; p 14:17.
(25) - Silberberg, Martin S. Chemistry: The Molecular Nature of Matter and Change, 4th ed.; McGraw-Hill Higher Education: Boston, MA, 2006, p 962.
(26) - Silberberg, Martin S. Chemistry: The Molecular Nature of Matter and Change, 4th ed.; McGraw-Hill Higher Education: Boston, MA, 2006, p 964.
(27) - Morgan, John W. and Anders, Edward, Proc. Natl. Acad. Sci. USA 77, 6973-6977 (1980)
(28) - Brownlow, Arthur. Geochemistry; Prentice-Hall, Inc.: Englewood Cliffs, NJ, 1979, pp 15-16.
(29) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; p 7:17.