Titanium - Ti, 22

Titanium has a melting point of 1660 +/- 10°C, boiling point of 3287°C, specific gravity of 4.54, with a valence of 2, 3, or 4. Pure titanium is a lustrous white metal with low density, high strength, and high corrosion resistance. It is resistant to dilute sulfuric and hydrochloric acids, moist chlorine gas, most organic acids, and chloride solutions. Titanium is only ductile when it is free of oxygen. Titanium burns in air and is the only element that burns in nitrogen. Titanium is dimorphic, with the hexagonal a form slowly changing to the cubic b form around 880°C. The metal combines with oxygen at red heat temperatures and with chlorine at 550°C. Titanium is as strong as steel, but it is 45% lighter. The metal is 60% heavier than aluminum, but it is twice as strong. 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 hgher than that of diamond. Natural titanium becomes highly radioactive upon bombardment with deuterons.

Since it is strong and resists acids it is used in many alloys. Titanium dioxide (TiO₂), a white pigment that covers surfaces very well, is used in paint, rubber, paper and many other materials. Also used in heat exchangers, airplane motors, bone pins and other things requiring light weight metals or metals that resist corrosion or high temperatures. Titanium oxide is used extensively in paints.