CHEMISTRY GLOSSARY

law of conservation of energy    →   zakon o očuvanju energije

Law of conservation of energy: In an isolated system energy can be transferred from one form to another but the total energy of the system remains constant.

partial pressure    →   parcijalni tlak

Partial pressure is a pressure that one component of gas mixture would have if it were alone in the same volume and at the same temperature as the mixture is in now.

photon    →   foton

Photon is an elementary particle of zero mass and spin 1/2. The photon is involved in electromagnetic interactions and is the quantum of electromagnetic radiation. The photon may also be regarded as a unit of energy equal to

where h is Planck constant and ν is the frequency of the radiation.

column chromatography    →   kromatografija u koloni

Column chromatography is generally used as a purification technique: it isolates desired compounds from a mixture. In column chromatography, the stationary phase, a solid adsorbent, is placed in a vertical column. The mobile phase, a liquid, is added to the top and flows down through the column by either gravity or external pressure. The mobile phase can be a gas or a liquid which gives rise to the two basic forms of chromatography, namely, gas chromatography (GC) and liquid chromatography (LC).

composition of ocean water    →   sastav oceanske vode

The proportions of the major constituents of ocean water are almost constant throughout the world. Salinity (total salt content) and the concentrations of individual chemical constituents in sea wateris given the units psu (practical salinity units). For most purposes one can assume that the new unit, psu, and the older unit, ‰, are synonymous.

The average composition of the ocean water is as shown on the following table.

Coulomb’s law    →   Coulombov zakon

Coulomb’s law is the statement that the force F between two electrical charges q₁ and q₂ separated by a distance r is

where ε_o is the permittivity of a vacuum, equal to

pK    →   pK

pK is the negative logarithm (base 10) of an equilibrium constant K.

quantum    →   kvant

Quantum is the smallest quantity of energy that can be emitted (or absorbed) in the form of electromagnetic radiation. Energy of a quantum (E) is equal to

where h is Planck constant and ν is the frequency of radiation.

salt fog chambers    →   slana komora

Salt fog chambers are designed for corrosive atmosphere testing. The samples being tested are inserted into the chamber and then the salt-containing solution is sprayed as a very fine fog mist over the samples. The temperature within the chamber is maintained constant (usually 35 °C). These test chambers are constructed of non-corrosive materials.

crude oil    →   sirova nafta

Crude oil (petroleum) is a fossil fuel formed from plant and animal remains many million of years ago. It is occasionally found in springs or pools but is usually drilled from wells beneath the earth’s surface. Crude oil is a mixture of hydrocarbons with small quantities of other chemicals such as sulphur, nitrogen and oxygen. Crude is the raw material which is refined into petrol, heating oil, jet fuel, propane, petrochemicals, and other products.