ATitanium is a chemical element that belongs to Group 4 (IVb) of the periodic table and is represented as (Ti) in the periodic table.Titanium is the ninth-most prevalent element (0.63% by mass) and the seventh-most abundant metal in the Earth’s crust. It is the 22nd element in the periodic table.
Titanium is a light transition metal with a white-silvery metallic appearance. It is glossy, durable, and resistant to corrosion. Pure titanium is not soluble in water, although it is soluble in concentrated acids. When exposed to high temperatures in the air, this metal generates a passive yet protective oxide layer (leading to corrosion resistance), but at normal temperature it resists tarnishing.
Interesting Science Videos
History of Titanium
- Titanium was found as an inclusion of a mineral in Cornwall, Great Britain, in 1791 by the priest and geologist William Gregor.
- In ilmenite, Gregor discovered the presence of a new element. When he discovered black sand beside a creek and discovered it was attracted by a magnet.
- Analyzing the sand, he discovered two metal oxides: iron oxide (which explains the magnetism) and 45.25% of a white metallic oxide he couldn’t identify.
- Recognizing that the mysterious oxide included a metal that did not match any known element, Gregor published his results in 1791.
- In 1795 the oxide was independently discovered by German Chemist Martin Heinrich Klaproth in a village in slovakia (then hungary).
- Klaproth found that it contained a new element and named it for the Titans of Greek mythology where it got its name ‘Titanium‘.
- After hearing about Gregor’s earlier discovery, he obtained a sample of manaccanite and confirmed that it contained titanium.
- The pure elemental metal was not made until 1910 by Matthew A. Hunter, who heated TiCl4 together with sodium in a steel bomb at 700-800°C.
- When Anton Eduard van Arkel and Jan Hendrik de Boer devised the iodide technique in 1925, they produced exceedingly pure titanium in tiny quantities by reacting with iodine and decomposing the generated fumes over a hot filament.
- The Soviet Union pioneered the use of titanium in military and submarine applications during the 1950s and 1960s.
- Now the 22nd element on the periodic table, titanium is useful in a wide range of industries due to its strength, corrosion resistance, and compatibility with the human body.
Occurrence of Titanium
- Titanium metal does not exist as a free element. It is the ninth most prevalent element in the earth’s crust. It is commonly found in igneous rocks and the sediments formed from them.
- It may be found in rutile (TiO2), ilmenite (FeTiO3), and sphene, as well as titanates. Numerous iron ore deposits can be found in the United States, Australia, Scandinavia, and Malaysia.
- It occurs in the minerals rutile, ilmenite, and sphene, and is present in titanates and in many iron ores. Titanium is present in ash of coal, in plants, and in human body.
- The metal was a laboratory curiosity until Kroll demonstrated in 1946 that titanium could be economically manufactured by reducing titanium tetrachloride with magnesium. This process is still widely used to produce metal. By decomposing the iodide, the metal may be refined.
Isotopes of Titanium
Natural titanium consists of five isotopes with atomic masses from 46 to 50. All are stable and are used for a wide range of studies and applications
| Isotope | Natural abundance (atom %) |
|---|---|
| 46Ti | 8.25 (3) |
| 47Ti | 7.44 (2) |
| 48Ti | 73.72 (3) |
| 49Ti | 5.41 (2) |
| 50Ti | 5.18 (2) |
- Ti-48 is used for the production of the radioisotope V-48 which is used in nutritional studies and for calibrating PET instrumentation.
- Ti-50 is utilized in the manufacture of super heavy elements by bombarding Lead or Bismuth targets with Ti-50.
- Ti-49 is used in the production of the radioisotope V-49.
Elemental Properties of Titanium
| Electronic Configuration | [ Ar ] 3d1 4s2 |
| Atomic Number | 22 |
| Atomic Weight | 47.90 g.mol -1 |
| State at 20°C | Solid |
| Group, Period, and Block | 4, 4, d block |
| Density | 4.51 g.cm-3 at 20°C |
| Ionic radius | 0.09 nm (+2) ; 0.068 nm (+4) |
| Van der Waals radius | 0.147 nm |
| Electron shells | 2,8,10,2 |
| Electrons | 22 |
| Protons | 22 |
| Neutrons in most abundant isotope | 26 |
Physical Properties of Titanium
- Titanium’s key properties are its low density, strong mechanical strength, and ease of processing. Titanium’s plasticity is primarily determined by its purity; the purer the titanium, the greater the plasticity.
- Titanium is resistant to corrosion and is unaffected by the atmosphere or ocean and it is not damaged at room temperature.
- Titanium is not easily corroded by sea water and is used in propeller shafts, rigging and other parts of boats that are exposed to seawater.
- Titanium is a key alloying element in steel and alloys and it has a density of 4.506-4.516 grams per cubic centimeter (20 ° C), which is greater than aluminum and lower than iron, copper, and nickel, yet it has the highest specific strength of any metal.
- Titanium is a strong, light metal. It is as strong as steel and twice as strong as aluminum, but is 45% lighter than steel and only 60% heavier than aluminum.
- Titanium metal is a paramagnetic substance with a magnetic permeability of 1.00004.
- Titanium has plasticity. The elongation of high-purity titanium can reach 50-60%.
- Titanium is not ferromagnetic, hence nuclear submarines made of it are not vulnerable to magnetic mine assaults.
- Titanium metal is considered to be physiologically inert. Pure titanium dioxide is reasonably clear, with an extremely high index of refraction and an optical dispersion higher than that of a diamond. Natural titanium becomes highly radioactive upon bombardment with deuterons.
| Color/physical appearance | Shiny, dark-gray metal |
| Melting point/freezing point | 1941 [1668 °C (3034 °F)] K |
| Boiling point | 3560 [3287 °C (5949 °F)] K |
| Density | 4.5 (g cm−3) (20 °C) |
| Malleability | Yes |
| Ductility | Yes |
| Electronegativity | 1.54 (Pauling Scale) 1.38 (Allen Scale) |
Chemical Properties of Titanium
- Titanium metal and its alloys, like aluminum and magnesium, oxidize instantly upon contact to air, forming a thin non-porous passivation layer that shields the bulk metal from further oxidation or corrosion.
- Titanium is resistant to dilute sulfuric and hydrochloric acids, chloride solutions, and the majority of organic acids.
- Titanium is corroded by concentrated acids.
- Titanium dioxide is formed when it combines with oxygen at 1,200 °C (2,190 °F) in air and 610 °C (1,130 °F) in pure oxygen.
Chemical Reaction of Titanium
- Reaction of titanium with air
An oxide layer covers the titanium metal, usually making it inert. However, as titanium begins to burn in air, it produces titanium dioxide (TiO2) and titanium nitride (TiN), both of which burn with a stunning white flame. Even pure nitrogen can be used to burn titanium metal to create titanium nitride.
Ti (s) + O2 (g) → TiO2 (s)
2Ti (s) + N2 (g) → TiN (s)
- Reaction of titanium with water
Titanium, will react with steam to generate titanium(IV) oxide, TiO2, and hydrogen, H.
Ti(s) + 2H2O(g) → TiO2(s) + 2H2(g)
- Reaction of titanium with the halogens
Titanium reacts with the halogens to form titanium(IV) halides upon warming. The reaction with fluorine requires heating to 200°C. So, titanium reacts with fluorine (F2), chlorine (Cl2), bromine (I2), and iodine (I2), to form respectively titanium(IV) bromide (TiF), titanium(IV) chloride (TiCl), titanium(IV) bromide (TiBr), and titanium(IV) iodide (TiI) respectively.
Ti (s) + 2F2 (g) → TiF4( s) [white]
Ti (s) + 2Cl2 (g) → TiCl4 (l) [colourless]
Ti (s) + 2Br2 (g) → TiBr4 (s) [orange]
Ti (s) + 2I2(g) → TiI4 (s) [dark brown]
- Reaction of titanium with acids
Dilute aqueous hydrofluoric acid, HF, reacts with titanium to form the complex anion [TiF6]3- together with hydrogen, H2.
2Ti(s) + 12HF(aq) → 2[TiF6]3-(aq) + 3H2(g) + 6H+(aq)
Titanium metal does not react with mineral acids at ambient temperature but does react with hot hydrochloric acid to form titanium(III) complexes.
- Reaction of titanium with bases
Titanium does not appear to react with alkalis under normal conditions, even when hot.
Uses of Titanium
- Titanium is used for alloying with other metals such as aluminum, molybdenum, iron, manganese, and others. Titanium alloys are utilized in applications that need lightweight strength and the ability to withstand extremes of temperature (for example, aerospace).
- Because of its chemical inertness, excellent coating power, opacity to UV radiation damage, and auto cleaning capacity, titanium dioxide is widely employed as a white pigment in exterior paints.
- Titanium dioxide once was utilized as a bleaching and pacifying agent in porcelain enamels, imparting a finishing touch of outstanding brightness.
- The metal is frequently used for components which must be exposed to seawater. A titanium anode coated with platinum may be used to provide cathodic corrosion protection from seawater.
- Because it is inert in the body, titanium metal has surgical applications.
- Titanium oxide pigments account for the largest use of the element. Titanium oxide is used in some cosmetics to disperse light such as in lipsticks.
- Since titanium does not react within the human body, it is used to create artificial hips, pins for setting bones and for other biological implants.
- Pure titanium oxide is relatively clear and is used to create titania, an artificial gemstone.
- Titanium has potential use in desalination plants for converting sea water into fresh water.
Health Effects of Titanium
There is no known biological role for titanium. It is not a poison metal and the human body can tolerate titanium in large doses. There is measurable titanium in the human body, and it has been estimated that humans consume roughly 0.8 mg/day, although the majority of it passes past us without being absorbed.
The toxicity of elemental titanium and titanium dioxide is minimal. Laboratory rats exposed to titanium dioxide by inhalation got little patches of dark-colored dust deposits in their lungs. Excessive exposure in humans might cause minor alterations in the lungs.
Effects of overexposure to titanium powder: Dust inhalation may cause tightness and pain in the chest, coughing, and difficulty in breathing. Contact with skin or eyes may cause irritation. Routes of entry: Inhalation, skin contact, eye contact.
Environmental Effects of Titanium
No environmental effects of titanium have been reported until this day. It possesses very low toxicity. But in a metallic powdered form, titanium metal poses a significant fire hazard and when heated in the air an explosion hazard.
Interesting Facts about Titanium
- After titanium was initially found, it took 119 years to even separate it into a pure sample.
- Additionally, it has the ability to “osseointegrate,” or join with bone tissue.
- During the Cold War, various nations accumulated titanium.
- Titanium is not just present on Earth. Satellite imagery of the moon’s surface in 2011 showed groupings of rock rich in titanium.
- The titanium-covered Guggenheim Museum in Spain.
A brief overview of the periodic table element number 22 – titanium. Watch out the video.
References
- https://periodictable.com/Elements/022/data.html
- https://pubchem.ncbi.nlm.nih.gov/element/Titanium#section=Information-Sources
- Buettner, K. M.; Valentine, A. M. (2012). “Bioinorganic Chemistry of Titanium”. Chemical Reviews. 112 doi:10.1021/cr1002886. PMID 22074443
- https://www.webelements.com/titanium/
- Hampel, Clifford A. (1968). The Encyclopedia of the Chemical Elements. Van Nostrand Reinhold. ISBN 978-0-442-15598-8.
- https://www.lenntech.com/periodic/elements/ti.html
- https://www.lenntech.com/periodic/elements/ti.html
- Mary Elvira Weeks, The discovery of the elements. XI. Some elements isolated with the aid of potassium and sodium: Zirconium, titanium, cerium, and thorium., J. Chem. Educ., 1932, p1231.
- https://www.britannica.com/science/titanium
- Greenwood, N. N.; Earnshaw, A. (1997). Chemistry of the Elements (2nd ed.). Oxford: Butterworth-Heinemann. ISBN 978-0-7506-3365-9.
