CHEMISTRY GLOSSARY

coke    →   koks

Coke is a hard, dry carbon substance produced by heating coal to a very high temperature in the absence of air. It is used in the manufacture of iron and steel.

colligative properties    →   koligativna svojstva

Colligative properties are properties which affect a solvent based on the number of molecules of solute present such as melting point, boiling point and osmotic pressure.

colorimetry    →   kolorimetrija

Colorimetry is a quantitative chemical analysis by colour using a colorimeter.

colloid    →   koloid

Colloids are systems in which there are two or more phases, with one (the dispersed phase) distributed in the other (the continuous phase). Moreover, at least one of the phases has small dimensions, in the range between 1 nm and 1 μm (10^-9 m – 10^-6 m). Dimension, rather than the nature of the material, is characteristic. In this size range, the surface area of the particle is large with respect to its volume so that unusual phenomena occur, e.g., the particles do not settle out of the suspension by gravity and are small enough to pass through filter membranes. Macromolecules (proteins and other high polymers) are at the lower limit of this range; the upper limit is usually taken to be the point at which the particles can be resolved in an optical microscope.

Colloidal particles may be gaseous, liquid, or solid, and occur in various types of suspensions:

Sols - dispersions of small solid particles in a liquid.

Emulsions - colloidal systems in which the dispersed and continuous phases are both liquids.

Gels - colloids in which both dispersed and continuous phases have a three-dimensional network throughout the material.

Aerosols - colloidal dispersions of liquid or solid particles in a gas.

Foams - dispersions of gases in liquids or solids.

colloid mill    →   koloidni mlin

Colloid mills are machines used to grind aggregates into very fine particles or to apply very high shearing within a fluid to produce colloid suspensions or emulsions in which the particle sizes are less than 1 micrometer. One type of colloid mill is called a disc mill, in which a mixture of a solid and liquid (or two liquids) is passed between two discs a small distance apart, which rotate very rapidly relative to each other. Applications of colloid mills occur in food processing, in paint manufacture, and in the pharmaceutical industry.

combustion    →   gorenje

Combustion is a phenomenon when a substance is combined with oxygen in the presence of a flame accompanied by the production of heat and light. Combustion requires a supply of both fuel and oxygen (air) and can take place in the open atmosphere such as an open fire, or in a closed system, such as a car engine.

complexometry    →   kompleksometrija

Complexometry is a volumetric analytic method which is based on titration of metal ion solutions with a substance that, combined with metal ions yields complex compounds, e.g. EDTA. The stoichiometric ratio of EDTA-metal in complexometric analyses is always 1:1, whatever the valency of the metal

contaminant    →   kontaminat

Contaminants are any physical, chemical, biological, or radiological substance or matter in water that may be harmful to human health or which degrade the palatability of water.

corticosteroid    →   kortikosteroid

Corticosteroids are general term for hormones produced by the adrenal gland. Includes cortisol and cortisone which regulate the use of nutrients in the body.

critical mass    →   kritična masa

Critical mass is the minimum mass of a fissionable material (²³⁵U or ²³⁹Pu) that will initiate an uncontrolled chain reaction as in an atomic bomb. The critical mass of pure ²³⁹Pu is about 4.5 kg, and of ²³⁵U about 15 kg.