Titanium is a transition metal located in group 4 and period number 4 in the periodic table. The atomic number of titanium is 22 whereas its atomic mass is 47.867. Titanium contains 22 electrons in its single neutral atom. The nucleus of titanium has 22 protons and 26 neutrons. It is represented by the symbol “Ti”.
Naming and History
The term “Titanium” is from the Greek word “Titan”. In Greek mythology, titans – the sons of the Earth goddess.
- Reverend William Gregor
In 1791, geologist Reverend William Gregor discovered the first titanium mineral, black sand known as menachanite in Cornwall, England. He observed that it was black sand with magnetic properties like gun powder. He further analyzed it and deduced the result that it consisted of oxides of iron in addition to an unknown metal.
He named that unknown metal “reddish-brown calx”.
- Martin Heinrich
In 1795, the famous German scientist Martin Heinrich in Hungary found titanium in mineral rutile. It was of red color just like the reddish calx of Gregor. He realized the red oxide in titanium of rutile and menachanite of Gregor was the same. He named it titanium after Titans – the sons of Earth.
- Mathew Hunter
In 1910, Mathew Hunter who was metallurgist, first isolated the pure titanium metal by heating titanium chloride with sodium in a pressure cylinder.
Occurrence of Titanium
Titanium does not occur free in nature but is the ninth most abundant element present in the Earth’s crust. It mostly occurs in igneous rocks and sediments rocks which are derivative of igneous rocks.
The major ores and minerals of titanium are ilmenite, titanite, anatase, rutile, brookite, leucoxene, perovskite, sphene, etc. The major suppliers of titanium to the world are Canada, Western Australia, Norway, South Africa and North America.
Properties of Titanium
Titanium is strong, hard, silvery–whitish, lustrous, corrosion-resistant, and a lightweight transition metal. Chemically, it shows many similarities with zirconium. In the aqueous phase, it shows similarities with chromium and vanadium. At high temperatures, it forms a protective oxide coating which gives it a corrosion-resistant nature, but at normal temperature, it resists tarnish.
It is insoluble in water but can dissolve in concentrated acids. On heating, titanium is malleable and ductile. On combining with halogens, or heating to obtain dioxide, metal burns in the air.
The melting point of titanium is 1668°C and its boiling point is 3287°C. It has a density of 4.5 grams per cubic centimeter and exists as a solid phase at room temperature.
Titanium in Biological Systems
There is no known significant role of titanium in biological systems. Titanium is considered to be non-toxic but some of its compounds are suspected to be carcinogenic.
Uses of Titanium
- Titanium has the strength of steel but is light in weight. Therefore, it is used in alloying. It is alloyed with aluminum, iron, and molybdenum. These alloys are used in aerospace applications such as space crafts, air crafts, missiles, etc.
- It is so resistant that after 4000 years in saltwater, corrosion only would have penetrated the thickness of metal into a thin sheet. That is why used in structures exposed to the sea such as ship hulls, shafts, etc.
- Titanium is used in bicycles, crutches, laptops, etc.
- Titanium oxide is used in paint pigments, plastics, and enamels.
- Titanium is used in biological implants, in joints such as ball and socket joint replacement, hips, pins for bone settings.
- Man-made gemstones (soft in nature) are made by using titanium.
- Titania is a white pigment used in toothpaste, food coloring, and sunscreen.
- Smokescreens are made by using titanium tetrachloride. This compound is also used to iridize glass.
- Titanium is an excellent infrared radiation reflector.
- It is also used in the desalination of plants.
Isotopes of Titanium
There are almost 18 known isotopes of titanium whose mass numbers range from 39 to 57. The most abundant naturally occurring isotope of titanium is Ti- 48 with 73.7%.