CHEMISTRY GLOSSARY

coulometry    →   kulometrija

Coulometry is a quantitative electrochemical analytical method which is based on measuring the quantity of electricity that has passed and on Faraday’s laws.

dolomite    →   dolomit

Dolomite is a carbonate mineral consisting of a mixed calcium-magnesium carbonate, CaCO₃·MgCO₃, crystallising in the rhombohedral system. It is usually white or colourless. The term is also used to denote a rock with a high ratio of magnesium to calcium carbonate.

ductility    →   rastezljivost

Ductility is a measure of a material’s ability to undergo appreciable plastic deformation before fracture; it may be expressed as percent elongation or percent area reduction from a tensile test.

effervescence    →   pjenušanje

Effervescence is the formation of gas bubbles in a liquid by a chemical reaction. An example of effervescence is the release of carbon dioxide which bubbles as a gas from the liquid when limestone chips, which are composed of calcium carbonate, are added to dilute hydrochloric acid.

electrochemical potential    →   elektrokemijski potencijal

Electrochemical potential is a measure of a metal to form ions in a liquid.

balance    →   vaga

Balance is an instrument to measure the mass (or weight) of a body. Balance beam type scales are the oldest type and measure weight using a fulcrum or pivot and a lever with the unknown weight placed on one end of the lever, and a counterweight applied to the other end. When the lever is balanced, the unknown weight and the counterweight are equal. The equal-arm balance consists of two identical pans hung from either end of a centrally suspended beam. The unequal-arm balance is made with one arm of the balance much longer than the other.

More modern substitution balances use the substitution principle. In this calibrated weights are removed from the single lever arm to bring the single pan suspended from it into equilibrium with a fixed counter weight. The substitution balance is more accurate than the two-pan device and enables weighing to be carried out more rapidly.

Electromagnetic force restoration balances also use a lever system but a magnetic field is used to generate the force on the opposite end of the lever and balance out the unknown mass. The current used to drive the magnetic coil is proportional to the mass of the object placed on the platform.

barometer    →   barometar

Barometer is an instrument that measures atmospheric pressure. A mercury barometer is a closed tube filled with mercury inverted in a mercury reservoir. The height of the mercury column indicates atmospheric pressure (with 1 atm = 760 mm of mercury). An aneroid barometer consists of an evacuated container with a flexible wall. When atmospheric pressure changes, the wall flexes and moves a pointer which indicates the changing pressure on a scale.

flame    →   plamen

Flame is a mixture of heat and light energy which occurs when sudden combustion occurs.

flotation    →   flotacija

Flotation is a procedure in which hydrophobic solid substances are separated from hydrophilic one using bubbles of air. If air is blow through a suspension, in which substances promoting easier creation of foam are added, bubbles of air are created which stick to the hydrophobic matter and carry it out to the surface.

gas thermometer    →   plinski termometar

Gas thermometer is a device for measuring temperature in which the working fluid is a gas.