CHEMISTRY GLOSSARY

alpha particle    →   alfa-čestica

Alpha particle is a helium nucleus emitted spontaneously from radioactive elements, both natural and manufactured. Its energy is in range 4-8 MeV and is dissipated in a very short path, i.e. a few centimetres of air or less than 0.005 mm of aluminium. As helium nucleus consists of two protons and two neutrons bound together as a stable entity the loss of an alpha particle involves a decrease in nucleon number of 4 and decrease of 2 in the atomic number, e.g.

A stream of alpha particles is known as an alpha ray or alpha-radiation.

beta particle    →   beta-čestica

Beta particle is a charged particle emitted from a radioactive atomic nucleus either natural or manufactured. The energies of beta particles range from 0 MeV to 4 MeV. They carry a single charge; if this is negative, the particle is identical with an electron; if positive, it is a positron.

An unstable atomic nucleus changes into a nucleus of the same mass number but different proton number with the emission of an electron and an antineutrino (or a positron and a neutrino)

elementary particle    →   elementarna čestica

Elementary particle is one of fundamental particles of which matter is composed, such as the electron, proton or neutron.

paraffin wax    →   parafinski vosak

Paraffin waxes are a mixture of solid alkanes. They are used in the production of candles.

paraffins    →   parafini

Paraffins are an obsolescent term for alkanes. Still widely used in the petrochemical industry.

paramagnetism    →   paramagnetizam

Paramagnetism is a type of magnetism characterised by a positive magnetic susceptibility, so that the material becomes weakly magnetised in the direction of an external field. The magnetisation disappears when the field in removed.

parchment paper    →   pergamentni papir

Parchment paper is impermeable paper obtained by dipping cellulosic paper in the sulphuric acid.

partial pressure    →   parcijalni tlak

Partial pressure is a pressure that one component of gas mixture would have if it were alone in the same volume and at the same temperature as the mixture is in now.

subatomic particles    →   subatomske čestice

Subatomic particles are the constituent parts of the atom, such as the electron, proton, neutron, etc.

wave-particle duality    →   valno-čestična dualnost

Wave-particle duality is an observation that electrons, photons, and other very small entities behave like particles in some experiments and like waves in others.