CHEMISTRY GLOSSARY

conduction    →   kondukcija

This process occurs most significantly in solids. The atoms or molecules in a solid state do not leave their mean positions, but continue to vibrate about their mean positions. They transfer heat energy from one atom to another. This happens because of the coupling between them due to mutually attractive forces.

bag filter    →   vrećasti filtar

Bag filter is a unit within a mechanical system that bellows in a bag form when air flows through, cleaning the air by collecting particles of foreign matter. This system of filtering is rated the most efficient- in a range of 92 % to 95 %. Vacuum cleaner have a cloth filter bag.

Bag filter system is an economical method of liquid filtration consisting of the pressure vessel, restrainer basket and micron rated filter bag. Liquid flow is from the inside to the outside of the bag - dirt is trapped inside the bag.

Balmer series    →   Balmerova serija

Balmer series, Balmer lines is a series of lines in the emission spectrum of hydrogen that involve transitions to the n=2 state from states with n>2.

blast furnace    →   visoka peć

Blast furnace is a furnace for smelting of iron from iron oxide ores (hematite, Fe₂O₃ or magnetite, Fe₃O₄). Coke, limestone and iron ore are poured in the top, which would normally burn only on the surface. The hot air blast to the furnace burns the coke and maintains the very high temperatures that are needed to reduce the ore to iron. The reaction between air and the fuel generates carbon monoxide. This gas reduces the iron(III) oxide in the ore to iron.

Because the furnace temperature is in the region of 1500 °C, the metal is produced in a molten state and this runs down to the base of the furnace.

The production of iron in a blast furnace is a continuous process. The furnace is heated constantly and is re-charged with raw materials from the top while it is being tapped from the bottom. Iron making in the furnace usually continues for about ten years before the furnace linings have to be renewed.

contaminant    →   kontaminat

Contaminants are any physical, chemical, biological, or radiological substance or matter in water that may be harmful to human health or which degrade the palatability of water.

dissolved substance    →   otopljena tvar

Dissolved substance is a solid, liquid or gas matter dissolved in a solvent. Depending upon the particle size of dissolved substance, solutions differ in properties and can be divided into real solutions (diameter of particles is smaller than 1 nm), colloid solutions (diameter of particles is from 1 nm to 200 nm) and suspensions (diameter of particles is greater than 200 nm).

drug    →   droga

Drug as a term is used for compounds that can cause addiction with an emphasis on narcotics. It is a biologically active compound or mixture used to cure, prevent, or detect disease, to control biological processes, or to alter the mental state.

Bohr atom    →   Bohrov atom

Bohr atom is a model of the atom that explains emission and absorption of radiation as transitions between stationary electronic states in which the electron orbits the nucleus at a definite distance. The Bohr model violates the Heisenberg uncertainty principle since it postulates definite paths and moment for electrons as they move around the nucleus. Modern theories usually use atomic orbitals to describe the behaviour of electrons in atoms.

Boyle’s law    →   Boyleov zakon

Boyle’s law (sometimes referred to as the Boyle-Mariott’s law) is the empirical law, exact only for an ideal gas, which states that the volume of a gas is inversely proportional to its pressure at constant temperature.

Charles’ law    →   Charlesov zakon

The volume of a fixed mass of gas at a constant pressure expand by the constant fraction of its volume at 0 °C. For each Celsius or kelvin degree its temperature is raised. For any ideal gas fraction it is approximately 1/273. This can be expressed by the equation

were V° is the volume at 0°C and V is its volume at t°C.

This is equivalent to the statement that the volume of a fixed mass of gas at a constant pressure is proportional to its thermodynamic temperature

This law also know as Gay-Lussac’s law.

An equation similar to the one given above applies to pressures for ideal gases: