CHEMISTRY GLOSSARY

ebullioscope    →   ebulioskop

Ebullioscope is device for determination of the boiling point.

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.

einsteinium    →   einsteinij

Einsteinium was discovered by Albert Ghiorso (USA) in 1952. Named in honour of Albert Einstein (1879-1955). It is synthetic radioactive metal. Einsteinium was made by bombarding uranium with neutrons.

electroanalytical chemistry    →   elektroanalitička kemija

Electroanalytical chemistry chemistry is the application of electrochemical cells and electrochemical techniques for chemical analysis. The analyte is dissolved in the electrolyte of the cell, and one can perform either qualitative analysis (determination of the type of constituents present) or quantitative analysis (determination of the amount of a given constituent).

chlorinity    →   klorinitet

Originally chlorinity (symbol Cl) was defined as the weight of chlorine in grams per kilogram of seawater after the bromides and iodides had been replaced by chlorides. To make the definition independent of atomic weights, chlorinity is now defined as 0.3285233 times the weight of silver equivalent to all the halides.

The Mohr-Knudsen titration method served oceanographers for more than 60 years to determine salinity from chlorinity. This modification of the Mohr method uses special volumetric glassware calibrated directly in chlorinity units. The Mohr method uses potassium chromate (K₂CrO₄) as an indicator in the titration of chloride ions chloride (plus a small amount of bromide and iodide) with a silver nitrate (AgNO₃) standard solution.

The other halides present are similarly precipitated.

A problem in the Mohr titration was that silver nitrate is not well suited for a primary standard. The Danish physicist Martin Knudsen (1871-1949) suggested that a standard seawater (Eau de mer Normale or Copenhagen Normal Water) be created and distributed to oceanographic laboratories throughout the world. This water was then used to standardize the silver nitrate solutions. In this way all chlorinity determinations were referred to one and the same standard which gave great internal consistency.

The relationship between chlorinity Cl and salinity S as set forth in Knudsen's tables is

In 1962, however, a better expression for the relationship between total dissolved salts and chlorinity was found to be

complexometry    →   kompleksometrija

Complexometry is a volumetric analytic method which is based on titration of metal ion solutions with a substance that, combined with metal ions yields complex compounds, e.g. EDTA. The stoichiometric ratio of EDTA-metal in complexometric analyses is always 1:1, whatever the valency of the metal

fermium    →   fermij

Fermium was discovered by Albert Ghiorso (USA) in 1953. Named in honour of Enrico Fermi. It is synthetic radioactive metal. Fermium was produced by bombarding lighter transuranium elements with still lighter particles or by neutron capture.

heterocyclic compounds    →   heterociklički spojevi

Heterocyclic compounds are cyclic compounds having as ring members atoms of at least two different elements, e.g., quinoline, 1,2-thiazole.

hydrophilic    →   hidrofilan

Hydrophilic is having a strong tendency to bind or absorb water, which results in swelling and formation of reversible gels. This property is characteristic of carbohydrates.

infrared spectroscopy    →   infracrvena spektroskopija

Infrared (IR) spectroscopy is a technique used for determining the structure (and sometimes concentration) of molecules by observing how infrared radiation is absorbed by a sample.