CHEMISTRY GLOSSARY

additive    →   aditivi

Additive is a substance added to a material to improve its properties in some way. Additives are often present in small amounts and are used for a variety of purposes, as in preventing corrosion, stabilizing polymers, and preserving and improving food.

ageing    →   starenje

Ageing is the physical and/or chemical change of a material with respect to time, under defined environmental conditions, leading to improvement or deterioration of properties.

allomerism    →   alomerija

Allomerism is the appearance of substances with different chemical composition but the same crystalline form.

analysis    →   analiza

Analysis. Chemical analysis is determination of the composition of a sample.

anode    →   anoda

Anode is the electrode at which oxidation occurs in a cell. Anions migrate to the anode.

Anode is a positive electrode on which reaction of oxidation is developed (loss of electrons).

antacid    →   antacid

Antacid is any mildly alkaline substance, such as sodium bicarbonate, taken internally or in water solution to neutralize excess stomach acidity.

antioxidant    →   antioksidans

Antioxidants are compounds that slow down oxidation processes that degrade foods, fuels, rubber, plastic, and other materials. Antioxidants like butylated hydroxyanisole (BHA), are added to food to prevent fats from becoming rancid and to minimize decomposition of vitamins and essential fatty acids; they work by scavenging destructive free radicals from the food.

activated charcoal    →   aktivni ugljen

Activated charcoal or activated carbon is charcoal that has been activated for adsorption by steaming or by heating in a vacuum. Charcoal is obtained by burning wood, nutshells, coconut husks or other materials. Charcoal becomes activated by heating it with steam to approximately 1000 °C in the absence of oxygen.

The chemical nature of amorphous carbon, combined with a high surface area makes it an ideal medium for the adsorption of organic chemicals. A single gram of such material can have 400 m² to 1 200 m² square meters of surface area. Activated charcoal is widely used to decolorize liquids, recover solvents, and remove toxins from water and air.

active site    →   aktivno mjesto

Active site is a pocket or crevice on an enzyme molecule that fits reactant molecules like a hand in a glove. The active site lowers the activation energy for reaction

azo compounds    →   azo-spojevi

Azo compounds are organic compounds containing the group -N=N- linking two other groups. They can be formed by reaction of a diazonium ion with a benzene ring.