CHEMISTRY GLOSSARY

technetium    →   tehnecij

Technetium was discovered by Carlo Perrier and Emilio Segre (Italy) in 1937. The origin of the name comes from the Greek word technikos meaning artificial. It is silvery-grey metal. Resists oxidation but tarnishes in moist air and burns in high oxygen environment. First synthetically produced element. Radioactive. Technetium is made first by bombarding molybdenum with deuterons (heavy hydrogen) in a cyclotron. Added to iron in quantities as low as 55 part-per-million transforms the iron into a corrosion-resistant alloy.

thermite    →   termit

Thermite is a stoichiometric powdered mixture of iron(II) oxide and aluminium for the reaction

The reaction is highly exothermic and the increase in temperature (over 2500 °C) is sufficient to melt the iron produced. It has been used for localized welding of steel object (e.g. railway lines) in the thermit process. Thermite is also used in incendiary bombs.

thorium    →   torij

Thorium was discovered by Jöns Jakob Berzelius (Sweden) in 1828. Named after Thor, the mythological Scandinavian god of war. It is heavy, grey, soft, malleable, ductile, radioactive metal. Tarnishes in air; reacts with water. Reacts violently with oxidants. Thorium is found in various minerals like monazite and thorite. Used in making strong alloys. Also in ultraviolet photoelectric cells. It is a common ingredient in high-quality lenses. Bombarded with neutrons make uranium-233, a nuclear fuel.

TNT    →   TNT

TNT (2,4,6-trinitrotoluene) is a coluorless to pale yellow, odorless crystalline compound. It is an explosive used in military shells, bombs, and grenades, in industrial uses, and in underwater blasting.

unununium    →   unununij

Unununium was discovered by S. Hofmann et al. collaboration at the Heavy Ion Research Laboratory (Gesellschaft für Schwerionenforschung, GSI) in Darmstadt, Germany in December 1994. The new element has not yet been officially named, but it is known as unununium, according to the system designated by the IUPAC for naming new elements. It is synthetic radioactive metal. In bombardments of ²⁰⁹Bi targets with ⁶⁴Ni using the velocity selector SHIP facility to discriminate in favor of the fused product, ²⁷²111 + ¹n, three sets of localized alpha-decay chains were observed with position-sensitive detectors.

uranium    →   uranij

Uranium was discovered by Martin Heinrich Klaproth (Germany) in 1789. Named after the planet Uranus. It is silvery-white, dense, ductile, malleable, radioactive metal. Resists alkalis; tarnishes in air; attacked by steam and acids. Radiotoxic. Uranium occurs in many rocks, but in large amounts only in such minerals as pitchblende and carnotite. For many centuries it was used as a pigment for glass. Now it is used as a fuel in nuclear reactors and in bombs.

X-rays    →   X-zrake

X-rays are electromagnetic radiation of shorter wavelength than ultraviolet radiation (10^-11 m to 10^-9 m or 0.01 nm to 1 nm) produced by bombardment of atoms by high-quantum-energy particles. X-rays can pass through many forms of matter and they are therefore used medically and industrially to examine the internal structure.