CHEMISTRY GLOSSARY

mass number    →   maseni broj

Mass number (A) is a characteristic property of a specific isotope of an element, equal to the sum of the number of protons and neutrons in the nucleus.

meitnerium    →   meitnerij

Meitnerium was discovered by Peter Armbruster, Gottfried Münzenber and their co-workers at the Heavy Ion Research Laboratory (Gesellschaft für Schwerionenforschung, GSI) in Darmstadt, Germany in 1982. Named in honour of Lise Meitner (1878-1968), the Austrian physicist. It is synthetic radioactive metal. Meitnerium was produced bybombarding bismuth-209 with iron-58.

electric field    →   električno polje

If a small amount of charge experience a force, there is an electric field in the vicinity. Electric field E is defined in terms of electrostatic force F that would be exerted on positive test charge q_p placed in the field:

SI unit for electric field is N C^-1, or V m^-1.

The electric field due to a point charge q at distance r from it given by:

where ε₀ is permittivity constant, and is ε_o=8.85×10^-12 C² N^-1 m^-2.

electrical double layer    →   električni dvosloj

Electrical double layer is the structure of charge accumulation and charge separation that always occurs at the interface when an electrode is immersed into an electrolyte solution. The excess charge on the electrode surface is compensated by an accumulation of excess ions of the opposite charge in the solution. The amount of charge is a function of the electrode potential. This structure behaves essentially as a capacitor. There are several theoretical models that describe the structure of the double layer. The three most commonly used ones are the Helmholtz model, the Gouy-Chapman model, and the Gouy-Chapman-Stern model.

electronegativity    →   elektronegativnost

Electronegativity is a parameter originally introduced by L. Pauling which describes, on a relative basis, the power of an atom to attract electrons. For example, in hydrogen chloride, the chlorine atom is more electronegative than the hydrogen and the molecule is polar, with a negative charge on the chlorine atom.

There are various ways of assigning values for the electronegativity of an element. Pauling electronegativities are based on bond dissociation energies using a scale in which fluorine, the most electronegative element, has the value 4 and francium, the lowest electronegative element, has the value 0.7.

neutrino    →   neutrino

Neutrino is a stable elementary particle in the lepton family. Neutrinos have zero (or at least near-zero) rest mass and spin 1/2.

neutron number    →   neutronski broj

Neutron number (N) is a characteristic property of a specific isotope of an element, equal to the number of neutrons in the nucleus.

nucleon    →   nukleon

Nucleon is a collective term for the proton and neutron.

nucleophile    →   nukleofil

Nucleophiles are negatively charged or bear a partial negative charge. Examples are lone pairs or a hydroxide ion.

nuclide    →   nuklid

Nuclide is a species of atoms in which each atom has identical atomic number Z and identical mass number A. For example, a carbon-14 (C-14 or ¹⁴C) nuclide is the nucleus of a carbon atom, which has six protons and eight neutrons.