CHEMISTRY GLOSSARY

boiling point    →   vrelište

Boiling point is the temperature at which the vapour pressure of a liquid is equal to the external pressure on the liquid. The standard boiling point is the temperature at which the vapour pressure of a liquid equals standard pressure (101 325 Pa).

boiling point elevation    →   povišenje vrelišta

Boiling point elevation is an elevation of the boiling point of a solvent is observed when substances are dissolved in it. The amount by which the boiling point is elevated is proportional to the number of molecules of solute and independent of their nature.

depression of freezing point    →   snižavanje ledišta

Depression of freezing point of a pure solvent is observed when substances are dissolved in it. The amount by which the freezing point is depressed is proportional to the number of molecules of solute and independent of their nature.

equivalence point    →   točka ekvivalencije

Eequivalence point is the point in a titration when enough titrant has been added to react completely with the analyte.

flash point    →   temperatura zapaljenja

Flash point is the lowest temperature at which a liquid or volatile solid gives off vapour sufficient to form an ignitable mixture with the air near the surface of the liquid or within the test vessel (NFPA).

freezing point    →   ledište

Freezing point is the temperature at which a liquid becomes a solid at normal atmospheric pressure.

See Melting point

critical point    →   kritična točka

In general, critical point is the point on the phase diagram of a two-phase system at which the two coexisting phases have identical properties and therefore represent a single phase. At the liquid-gas critical point of a pure substance, the distinction between liquid and gas vanishes, and the vapour pressure curve ends. The coordinates of this point are called the critical temperature and critical pressure. Above the critical temperature it is not possible to liquefy the substance.

normal boiling point    →   normalno vrelište

Normal boiling point is a temperature at which pressure of liquid vapour is 101 325 Pa.

point-like object    →   materijalna točka

Point-like object is an expression, usual in kinematics: a point-like object (or a particle) is an object with dimensions, which can be neglected while considering its motion.

isoelectric point    →   izoelektrična točka

Isoelectric point (pI or IEP) is the pH of a solution or dispersion at which the net charge on the molecules or colloidal particles is zero. In electrophoresis there is no motion of the particles in an electric field at the isoelectric point. The net charge (the algebraic sum of all the charged groups present) of any amino acid, peptide or protein, will depend upon the pH of the surrounding aqueous environment. For example, alanine can have a charge of +1, 0, or -1, depending on the pH of the solution in which it is dissolved.