CHEMISTRY GLOSSARY

silver coulometer    →   srebrni kulometar

Silver coulometer consists of a platinum vessel which acts as a cathode and contains a solution of pure silver nitrate as an electrolyte (c(AgNO₃) = 1 mol/L). A rod of pure silver enclosed in a porous pot acts as the anode. The current density at the anode should not exceed 0.2 Acm^-2. After electrolysis, the electrolyte is taken out and the platinum vessel is washed, dried and weighed. The increase in the weight gives the amount of silver deposited (96500 C of electricity deposits 107.88 g of silver). From the mass of the silver deposited, the coulomb involved in the reaction can be calculated.

coulometer    →   kulometar

Coulometer is a type of electrolysis cell which is used for measuring the quantity of one element released during electrolysis.

actinium    →   aktinij

Actinium was discovered by André Debierne (France) in 1899. The origin of the name comes from the Greek word aktinos meaning ray. It is heavy, silvery-white, very radioactive metal. Reacts with water. Glows in the dark. Actinium is extremely rare, found in all uranium ores. Usually obtained by treating radium with neutrons in a reactor.

alpaca    →   alpaka

Alpaca (alpaka) or Nickel Silver is the generic name for any of a range of non-precious bright silvery-grey metal alloys, composed of copper, nickel and zinc. Despite its name it contains no real silver. It is also commonly called German Silver.

There are many different formulations of alloys which fall within the general term of Nickel Silver. All contain copper, nickel and zinc, while some formulations may additionally include antimony, tin, lead or cadmium. A representative formulation is 65 % copper, 18 % nickel, 17 % zinc. Nickel Silver is widely used for the commercial production of industrial components, housewares, flatware and cutlery, and as the metal substrate for silver-plated goods.

aluminium    →   aluminij

Aluminium was discovered by Friedrich Wöhler (Germany) in 1827. The origin of the name comes from the Latin word alumen meaning alum. It is soft, lightweight, silvery-white metal. Exposed surfaces quickly form protective oxide coating. Metal reacts violently with oxidants. Third most abundant element in the earth’s crust. Aluminium is the most abundant metal to be found in the earth’s crust, but is never found free in nature. Aluminium is obtained by electrolysis from bauxite. Used for many purposes from airplanes to beverage cans. Too soft in its pure form so less than 1 % of silicon or iron is added, which hardens and strengthens it.

americium    →   americij

Americium was discovered by Glenn T. Seaborg, Ralph A. James, Stanley G. Thompson and Albert Ghiorso (USA) in 1944. Named for the American continent. It is silvery-white, artificially produced radioactive metal. Americium was produced by bombarding plutonium with neutrons. Americium-241 is currently used in smoke detectors.

arsenic    →   arsen

Arsenic was discovered by Albertus Magnus (Germany) in 1250. The origin of the name comes from the Greek word arsenikon meaning yellow orpiment. It is steel-grey, brittle semi-metal. Resists water, acids and alkalis. Tarnishes in air, burns in oxygen. Highly toxic by inhalation or ingestion. Arsenic is found in mispickel (arsenopyrite). Many of its compounds are deadly poison and used as weed killer and rat poison. Used in semiconductors. Some compounds, called arsenides, are used in the manufacture of paints, wallpapers and ceramics.

berkelium    →   berkelij

Berkelium was discovered by Stanley G. Thompson, Albert Ghiorso and Glenn T. Seaborg (USA) in 1949. Named after Berkeley, a city in California, home of the University of California, USA. It is synthetic radioactive metal. Berkelium was made by bombarding americium with alpha particles.

californium    →   kalifornij

Californium was discovered by Stanley G. Thompson, Kenneth Street Jr. and Albert Ghiorso (USA) in 1950. Named after the State and University of California, USA. It is synthetic radioactive metal. Powerful neutron emitter. Californium was made by bombarding curium with helium ions.

curium    →   kurij

Curium was discovered by Glenn T. Seaborg, Ralph A. James and Albert Ghiorso (USA) in 1944. Named in honour of Pierre and Marie Curie. It is silvery, malleable, synthetic radioactive metal. So radioactive it glows in the dark. Curium was made by bombarding plutonium with helium ions.