CHEMISTRY GLOSSARY

calcination    →   kalciniranje

Calcination is a process of driving out crystal water from crystal salts by heating.

cementation    →   cementacija

Cementation is any metallurgical process in which the surfaces of a metal is impregnated by some other substance, especially an obsolete process for making steel by heating bars of wrought iron to red heat for several days in a bed of charcoal.

chemical    →   kemikalija

Chemicals are a common name for all chemical products or substances prepared by means of chemical-technologic processes.

chemical corrosion    →   kemijska korozija

Chemical corrosion is a damaging process of some materials with a chemical agent.

bomb calorimeter    →   kalorimetrijska bomba

Bomb calorimeter is a type of constant-volume calorimeter used in measuring the heat of combustion of samples which can be burned in oxygen. Four essential parts are required in any bomb calorimeter:

1. a bomb or vessel in which the combustible charges can be burned,
2. a bucket or container for holding the bomb in a measured quantity of water, together with a stirring mechanism,
3. an insulating jacket to protect the bucket from transient thermal stresses during the combustion process, and
4. a thermometer or other sensor for measuring temperature changes within the bucket.

Born-Haber cycle    →   Born-Haberov kružni proces

Born-Haber cycle is a cycle of reactions used for calculating the lattice energies of ionic crystalline solids. For a compound MX, the lattice energy is the enthalpy of the reaction

The standard enthalpy of formation of the ionic solid is the enthalpy of the reaction

The cycle involves equating this enthalpy (which can be measured) to the sum of the enthalpies of a number of steps proceeding from the elements to the ionic solid. The steps are:

1) Atomization of the metal

2) Atomization of the nonmetal

3) Ionisation of the metal

This is obtained from the ionisation potential.

4) Ionisation of the nonmetal

This is electron affinity.

5) Formation of the ionic solids

Equation of the enthalpies gives

from which ΔH_L can be found.

chemical engineering    →   kemijsko inženjerstvo

Chemical engineering is the branch of engineering that is concerned with the design, construction and operation of the plants and machinery used in industrial chemical processes.

coagulation    →   koaguliranje

Coagulation is a process of colloid particles merging into bigger ones. By removing the charge form a colloid ion, by increasing the temperature or by increasing electrolyte concentration, colloid particles will gather into bigger groups precipitate will emerge. Precipitate that is formed in this way (coagulate) is amorphic and considerably polluted with adsorbed pollutants.

coal    →   ugljen

Coal is a black or brownish-black, combustible sedimentary rock, with 30 % (lignite) to 98 % (anthracite) carbon by weight, mixed with various amounts of water and small amounts of sulfur and nitrogen compounds. It is formed from plant matter that decayed in swamps and bogs that has been compressed and altered by geological processes over millions of years. Coal is primarily used as a fuel.

Butler-Volmer equation    →   Butler-Volmerova jednadžba

Butler-Volmer equation is an activation controlled reaction, the one for which the rate of reaction is controlled solely by the rate of the electrochemical charge transfer process, which is in turn an activation-controlled process. This gives rise to kinetics that are described by the Butler-Volmer equation:

where i_o is exchange current density, η is overpotential (η = E - E_o), n is number of electrons, α_A is anodic transfer coefficient, and α_C is cathodic transfer coefficient