CHEMISTRY GLOSSARY

equation of state    →   jednadžba stanja

Equation of state is an equation relating the pressure, volume, and temperature of a substance or system. Equation of state for ideal gas

where p is pressure, V molar volume, T temperature, and R the molar gas constant (8.314 JK^-1mol^-1).

explosion    →   eksplozija

Explosion is a rapid violent chemical reaction that produces large amounts of gas and heat, accompanied by light, sound and a high-pressure shock wave.

critical temperature    →   kritična temperatura

Critical temperature is the temperature of the liquid-vapour critical point, that is, the temperature above which a gas cannot be liquefied by an increase of pressure.

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.

cryogenic fractionation    →   kriogena frakcinacija

Cryogenic fractionation is a process of separation of gases by cooling them until they enter their liquid state. Large scale gas production companies use this method to produce liquid oxygen, liquid nitrogen etc. Gases have different boiling points (the temperature at which they change from liquid to gas). Oxygen has a boiling point of -183 °C, and nitrogen a boiling point of -195.8 °C. Therefore by cooling the gas mixture to -183 °C, the oxygen can be collected as liquid and the nitrogen remains its gaseous form.

Dalton’s law    →   Daltonov zakon

Dalton’s law of partial pressure says that the total pressure eof gaseous mixture is equal to the sum of all gases partial pressures which make that mixture on the condition that they do not interact.

For example, if dry oxygen gas at 900 hPa is saturated with water vapor at 56 hPa, the pressure of the wet gas is 956 hPa.

filter    →   filtar

Filter is a device for separating solid particles from a liquid or a gas. The simplest laboratory filter for liquids is a funnel in which a cone of paper (filter paper) is placed. Special containers with a porous base of sintered glass are also used.

flashback    →   uskakanje plamena

Flashback occurs when the flame in a gas torch burns back into the torch or hose; this is often accompanied by a hissing or squealing sound, and a pointed or smoky flame.

fluid mechanics    →   mehanika fluida

Fluid mechanics is the study of various properties of the fluid (liquids and gases): velocity, pressure, density and temperature, as functions of space and time.

Dewar flask    →   Dewarova posuda

Dewar flask or vacuum bottle is a container for storing hot or cold substances. It consists of two flasks, one placed inside the other, with a vacuum between. The vacuum prevents the conduction of heat from one flask to the other. For greater efficiency the flasks are silvered to reflect heat. The substance to be kept hot or cold, e.g., liquid air, is contained in the inner flask. The flask is named after British chemist and physicist Sir James Dewar (1842-1923). Dewar invented the Dewar flask in 1892 to aid him in his work with liquid gases. The common thermos bottle is an adaptation of the Dewar flask.