CHEMISTRY GLOSSARY

ununbium    →   ununbij

Ununbium was discovered by S. Hofmann et al. collaboration at the Heavy Ion Research Laboratory (Gesellschaft für Schwerionenforschung, GSI) in Darmstadt, Germany in February 1996. The new element has not yet been officially named, but it is known as ununbium, according to the system designated by the IUPAC for naming new elements. It is synthetic radioactive metal. Using the electromagnetic velocity filter SHIP, fusion-like residues of the reaction of ⁷⁰Zn with enriched ²⁰⁸Pb targets were measured. Two chains of localized alpha-emitters were identified as originating with ²⁷⁷112 + ¹n.

ununquadium    →   ununkvadij

The discovery of ununquadium was reported informally in January 1999 following experiments towards the end of December 1998 involving scientists at Dubna (Joint Institute for Nuclear Research) in Russia and the Lawrence Livermore National Laboratory, USA. The new element has not yet been officially named, but it is known as ununquadium, according to the system designated by the IUPAC for naming new elements. It is synthetic radioactive metal. Only few atoms of element 114 (²⁸⁹114) has ever been made (through a nuclear reaction involving fusing a calcium atom with a plutonium atom) isolation of an observable quantity has never been achieved.

unununium    →   unununij

Unununium was discovered by S. Hofmann et al. collaboration at the Heavy Ion Research Laboratory (Gesellschaft für Schwerionenforschung, GSI) in Darmstadt, Germany in December 1994. The new element has not yet been officially named, but it is known as unununium, according to the system designated by the IUPAC for naming new elements. It is synthetic radioactive metal. In bombardments of ²⁰⁹Bi targets with ⁶⁴Ni using the velocity selector SHIP facility to discriminate in favor of the fused product, ²⁷²111 + ¹n, three sets of localized alpha-decay chains were observed with position-sensitive detectors.

work    →   rad

Work is the energy required to move an object against an opposing force. Work is usually expressed as a force times a displacement.

When a constant force F acts on a point-like object while the object moves through a displacement s, the force does work W on the object. If force and displacement are at a constant angle Θ to each other, the work is expressed by the scalar product of these two vectors:

When the force F on a point-like object is not constant that is, it depends on the position of the object, the work done by force while object moves from initial position with coordinates (x_i, y_i, z_i) to final position with coordinates (x_f, y_f, z_f)is given by expression:

Where F_x, F_y and F_z are scalar components of the force.

SI unit for work is joule (J); 1 J = 1 Nm = 1 kg m² s^-2. The electron-volt (eV) is commonly used in atomic and nuclear physics.

Schrotter apparatus for determination of CO2    →   Schrotterova aparatura za određivanje CO2

Schrötter decomposition apparatus (Schrötter's alkalimeter) is used to determining the carbonate content in samples of limestone, gypsum, dolomite, or baking powder by loss of weight. The apparatus is named after the Austrian chemist Anton Schrötter von Kristelli (1802-1875), who devised it in 1871. The size of the filled apparatus (apparatus is 16 cm high) is such that it weights less than 75 g, and can be placed on the pan of an analytical balance.

Procedure: Weigh about 0.5 g of the powdered carbonate sample and introduce it into the decomposition flask C. Pour into the drying tube A 2-3 mL of concentrated sulphuric acid (H₂SO₄), and to the dropping funnel B add about 10-15 mL of hydrochloric acid (w(HCl) = 15 %). Weigh the whole apparatus. Open the upper taps of both parts and allow the hydrochloric acid from B to run slowly down on to the powdered sample. The evolved CO₂ escapes through the strong sulphuric acid and is thus thoroughly dried. When further addition of acid produces no more evolution of CO₂, warm the apparatus up to 80 °C so as to expel the CO₂ from the solution. Connect the upper tap of the drying tube A to a water pump and draw a slow current of air through the apparatus until completely cool. Open the upper taps for a moment to equalize the internal and external pressure and weight the apparatus again. The weight loss is equal to the weight of carbon dioxide liberated from the carbonates.