CHEMISTRY GLOSSARY

decomposing    →   raščinjavanje

Decomposing in analytical chemistry means that a certain substance is converted, by melting it with a suitable melting medium (sodium carbonate, sodium hydroxide, sodium peroxide, ...) in the kind of compound which will afterwards that dissolve in water, acid or base very easily.

dehydration    →   dehidracija

Dehydration is the removal of water from a substance

dehydrogenation    →   dehidrogenacija

Dehydrogenation is a chemical reaction in which hydrogen is removed from a compound. Dehydrogenation of organic compounds converts single carbon-carbon bonds into double bonds. It is usually affected by means of a metal catalyst or in biological systems by enzyme dehydrogenases.

desalination    →   desalinizacija

Desalination is the removal of dissolved salts from seawater.

deuterium    →   deuterij

Deuterium is an isotope of hydrogen that contains one neutron and one proton in its nucleus.

deuterium lamp    →   deuterijeva svjetiljka

Deuterium or hydrogen lamp is used as a source of continuous radiation in UV part of the spectrum.

boron    →   bor

Boron compounds have been known for thousands of years, but the element was not discovered until 1808 by Sir Humphry Davy (England) and independently by Joseph-Louis Gay-Lussac (France) and L. J. Thenard (France). The origin of the name comes from the Arabic word buraq and the Persian word burah meaning boraks. It is hard, brittle, lustrous black semimetal. Unreactive with oxygen, water, alkalis or acids. Combines with most metals to form borides. Boron is obtained from kernite, a kind of borax (Na₂B₄O₇·10H₂O). High purity boron is produced by electrolysis of molten potassium fluroborate and potassium chloride (KCl). Amorphous boron is used in pyrotechnic flares to provide a distinctive green color and in rockets as an igniter.

brass    →   mjed

Brasses are alloys of copper and zinc (generally 5 % to 40 %). Brass has been known to man since prehistoric times, long before zinc itself was discovered. It was produced by melting copper together with calamine, a zinc ore. Its ductility reaches a maximum with about 30 % zinc and its tensile strength with 45 % although this property varies greatly with the mechanical and heat treatment of the alloy. Typical applications included gears, plumbing ware fittings, adapters, valves and screw machine products. The French horn is a valved brass wind instrument.

Brass may contain small amounts of other alloying elements, such as aluminum, lead, tin, or nickel. Lead can be added as an alloying element resulting in a brass that can be rapidly machined and produces minimal tool wear. Additions of aluminium, iron and manganese to brass improve strength, whilst silicon additions improve wear resistance. Brass containing tin (< 2 % ) is less liable to corrosion in seawater; it is sometimes called naval brass and is used in naval construction.

bromine    →   brom

Bromine was discovered by Antoine J. Balard (France) in 1826. The origin of the name comes from the Greek word bromos meaning stench. It is reddish-brown liquid with suffocating, irritating fumes. Gives off poisonous vapour. Causes severe burns. Oxidizer. Bromine occurs in compounds in sea water. It was once used in large quantities to make a compound that removed lead compound build up in engines burning leaded gasoline. Now it is primarily used in dyes, disinfectants and photographic chemicals.

dilution    →   razrjeđivanje

Dilution is the action of diluting or reducing the strength or concentration of a liquid, usually by the addition of water.