TITANIUM

Introduction

Atomic Number: 22
Group: 4 or IV B
Atomic Weight: 47.867
Period: 4
CAS Number: 7440-32-6

Classification

Chalcogen
Halogen
Noble Gas
Lanthanoid
Actinoid
Rare Earth Element
Platinum Group Metal
Transuranium
No Stable Isotopes
Solid
Liquid
Gas
Solid (Predicted)

Description • Uses/Function

Discovered by Gregor in 1791; named by Klaproth in 1795. Impure titanium was prepared by Nilson and Pettersson in 1887; however, thepure metal (99.9%) was not made until 1910 by Hunter by heating TiCl4 with sodium in a steel bomb. Titanium is present in meteorites and in the sun.Rocks obtained during the Apollo 17 lunar mission showed presence of 12.1% TiO2. Analyses of rocks obtained during earlier Apollo missions showlower percentages. Titanium oxide bands are prominent in the spectra of M-type stars. The element is the ninth most abundant in the crust of the earth.Titanium is almost always present in igneous rocks and in the sediments derived from them. It occurs in the minerals rutile, ilmenite, and sphene, andis present in titanates and in many iron ores. Deposits of ilmenite and rutile are found in Florida, California, Tennessee, New York, and elsewhere.Titanium is present in the ash of coal, in plants, and in the human body. The metal was a laboratory curiosity until Kroll, in 1946, showed that titaniumcould be produced commercially by reducing titanium tetrachloride with magnesium. This method is largely used for producing the metal today. Themetal can be purified by decomposing the iodide. Titanium, when pure, is a lustrous, white metal. It has a low density, good strength, is easily fabricated,and has excellent corrosion resistance. It is ductile only when it is free of oxygen. The metal burns in air and is the only element that burns in nitrogen.Titanium is resistant to dilute sulfuric and hydrochloric acid, most organic acids, moist chlorine gas, and chloride solutions. Natural titanium consistsof five isotopes with atomic masses from 46 to 50. All are stable. Fifteen other unstable isotopes are known. The metal is dimorphic. The hexagonalalpha form changes to the cubic beta form very slowly at about 880°C. The metal combines with oxygen at red heat, and with chlorine at 550°C. Titaniumis important as an alloying agent with aluminum, molybdenum, manganese, iron, and other metals. Alloys of titanium are principally used for aircraftand missiles where lightweight strength and ability to withstand extremes of temperature are important. Titanium is as strong as steel, but 45% lighter.It is 60% heavier than aluminum, but twice as strong. Titanium has potential use in desalination plants for converting sea water into fresh water. Themetal has excellent resistance to sea water and is used for propeller shafts, rigging, and other parts of ships exposed to salt water. A titanium anodecoated with platinum has been used to provide cathodic protection from corrosion by salt water. Titanium metal is considered to be physiologicallyinert; however, titanium powder may be a carcinogenic hazard. When pure, titanium dioxide is relatively clear and has an extremely high index ofrefraction with an optical dispersion higher than diamond. It is produced artificially for use as a gemstone, but it is relatively soft. Star sapphires andrubies exhibit their asterism as a result of the presence of TiO2. Titanium dioxide is extensively used for both house paint and artist’s paint, as it ispermanent and has good covering power. Titanium oxide pigment accounts for the largest use of the element. Titanium paint is an excellent reflectorof infrared, and is extensively used in solar observatories where heat causes poor seeing conditions. Titanium tetrachloride is used to iridize glass. Thiscompound fumes strongly in air and has been used to produce smoke screens. The price of titanium metal (99.8%) is about $550/kg. 1

• "A number of transition metals (Ti, Zr, Hf, V, Nb, Ta, Mo, W) form interstitial carbides of composition MC and, in some cases, M2C. These carbides have extremely high melting points; they are very hard, and they are good electrical conductors." 2

Physical Properties

Melting Point:3*  1668 °C = 1941.15 K = 3034.4 °F
Boiling Point:3* 3287 °C = 3560.15 K = 5948.6 °F
Sublimation Point:3 
Triple Point:3 
Critical Point:3 
Density:4  4.506 g/cm3

* - at 1 atm

Electron Configuration

Electron Configuration: [Ar] 4s2 3d2
Block: d
Highest Occupied Energy Level: 4
Valence Electrons: 

Quantum Numbers:

n = 3
ℓ = 2
m = -1
ms = +½

Bonding

Electronegativity (Pauling scale):5 1.54
Electropositivity (Pauling scale): 2.46
Electron Affinity:6 0.079 eV
Oxidation States: +4,3,2
Work Function:7 4.10 eV = 6.5682E-19 J

Ionization Potential   eV 8  kJ/mol  
1 6.8281    658.8
2 13.5755    1309.8
3 27.4917    2652.5
4 43.2672    4174.6
5 99.3    9581.0
6 119.53    11532.9
7 140.8    13585.1
Ionization Potential   eV 8  kJ/mol  
8 170.4    16441.1
9 192.1    18534.8
10 215.92    20833.1
11 265.07    25575.4
12 291.5    28125.5
13 787.84    76015.0
14 863.1    83276.5
Ionization Potential   eV 8  kJ/mol  
15 941.9    90879.5
16 1044    100730.7
17 1131    109124.9
18 1221    117808.6
19 1346    129869.2
20 1425.4    137530.2
21 6249    602936.7
22 6625.82    639294.3

Thermochemistry

Specific Heat: 0.523 J/g°C 9 = 25.034 J/mol°C = 0.125 cal/g°C = 5.983 cal/mol°C
Thermal Conductivity: 21.9 (W/m)/K, 27°C 10
Heat of Fusion: 15.45 kJ/mol 11 = 322.8 J/g
Heat of Vaporization: 421 kJ/mol 12 = 8795.2 J/g
State of Matter Enthalpy of Formation (ΔHf°)13 Entropy (S°)13 Gibbs Free Energy (ΔGf°)13
(kcal/mol) (kJ/mol) (cal/K) (J/K) (kcal/mol) (kJ/mol)
(s alpha) 0 0 7.33 30.66872 0 0
(s beta) 1.433 5.995672 8.691 36.363144 1.026 4.292784

Isotopes

Nuclide Mass 14 Half-Life 14 Nuclear Spin 14 Binding Energy
38Ti 38.00977(27)# <120 ns 0+ 281.11 MeV
39Ti 39.00161(22)# 31(4) ms [31(+6-4) ms] 3/2+# 296.64 MeV
40Ti 39.99050(17) 53.3(15) ms 0+ 314.96 MeV
41Ti 40.98315(11)# 80.4(9) ms 3/2+ 329.55 MeV
42Ti 41.973031(6) 199(6) ms 0+ 346.93 MeV
43Ti 42.968522(7) 509(5) ms 7/2- 359.66 MeV
44Ti 43.9596901(8) 60.0(11) a 0+ 376.12 MeV
45Ti 44.9581256(11) 184.8(5) min 7/2- 385.12 MeV
46Ti 45.9526316(9) STABLE 0+ 398.78 MeV
47Ti 46.9517631(9) STABLE 5/2- 407.78 MeV
48Ti 47.9479463(9) STABLE 0+ 419.58 MeV
49Ti 48.9478700(9) STABLE 7/2- 427.65 MeV
50Ti 49.9447912(9) STABLE 0+ 438.52 MeV
51Ti 50.946615(1) 5.76(1) min 3/2- 444.73 MeV
52Ti 51.946897(8) 1.7(1) min 0+ 452.80 MeV
53Ti 52.94973(11) 32.7(9) s (3/2)- 458.07 MeV
54Ti 53.95105(13) 1.5(4) s 0+ 464.28 MeV
55Ti 54.95527(16) 490(90) ms 3/2-# 468.63 MeV
56Ti 55.95820(21) 164(24) ms 0+ 473.90 MeV
57Ti 56.96399(49) 60(16) ms 5/2-# 477.32 MeV
58Ti 57.96697(75)# 54(7) ms 0+ 482.59 MeV
59Ti 58.97293(75)# 30(3) ms (5/2-)# 485.08 MeV
60Ti 59.97676(86)# 22(2) ms 0+ 489.42 MeV
61Ti 60.98320(97)# 10# ms [>300 ns] 1/2-# 490.97 MeV
62Ti 61.98749(97)# 10# ms 0+ 495.32 MeV
63Ti 62.99442(107)# 3# ms 1/2-# 496.87 MeV
Values marked # are not purely derived from experimental data, but at least partly from systematic trends. Spins with weak assignment arguments are enclosed in parentheses. 14

Reactions

Abundance

Earth - Source Compounds: oxides 16
Earth - Seawater: 0.001 mg/L 17
Earth -  Crust:  5650 mg/kg = 0.565% 17
Earth -  Mantle:  0.18% 18
Earth -  Total:  820 ppm 19
Mercury -  Total:  630 ppm 19
Venus -  Total:  850 ppm 19
Chondrites - Total: ~2600 (relative to 106 atoms of Si) 20

Compounds

Prices





Safety Information


Material Safety Data Sheet - ACI Alloys, Inc.

For More Information

External Links:

Sources

(1) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; p 4:32-4:33.
(2) - Jolly, William L. The Chemistry of the Non-Metals; Prentice-Hall: Englewood Cliffs, New Jersey, 1966; p 119.
(3) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; p 4:132.
(4) - Lide, David R. CRC Handbook of Chemistry and Physics, 84th ed.; CRC Press: Boca Raton, FL, 2002; p 4:39-4:96.
(5) - Dean, John A. Lange's Handbook of Chemistry, 11th ed.; McGraw-Hill Book Company: New York, NY, 1973; p 4:8-4:149.
(6) - Lide, David R. CRC Handbook of Chemistry and Physics, 84th ed.; CRC Press: Boca Raton, FL, 2002; p 10:147-10:148.
(7) - Speight, James. Lange's Handbook of Chemistry, 16th ed.; McGraw-Hill Professional: Boston, MA, 2004; p 1:132.
(8) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; p 10:178 - 10:180.
(9) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; p 4:133.
(10) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; pp 6:193, 12:219-220.
(11) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; pp 6:123-6:137.
(12) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; pp 6:107-6:122.
(13) - Dean, John A. Lange's Handbook of Chemistry, 12th ed.; McGraw-Hill Book Company: New York, NY, 1979; p 9:4-9:94.
(14) - Atomic Mass Data Center. http://amdc.in2p3.fr/web/nubase_en.html (accessed July 14, 2009).
(15) - Swaddle, T.W. Inorganic Chemistry; Academic Press: San Diego, 1997; p 382.
(16) - Silberberg, Martin S. Chemistry: The Molecular Nature of Matter and Change, 4th ed.; McGraw-Hill Higher Education: Boston, MA, 2006, p 965.
(17) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; p 14:17.
(18) - Silberberg, Martin S. Chemistry: The Molecular Nature of Matter and Change, 4th ed.; McGraw-Hill Higher Education: Boston, MA, 2006, p 962.
(19) - Morgan, John W. and Anders, Edward, Proc. Natl. Acad. Sci. USA 77, 6973-6977 (1980)
(20) - Brownlow, Arthur. Geochemistry; Prentice-Hall, Inc.: Englewood Cliffs, NJ, 1979, pp 15-16.