CHEMISTRY GLOSSARY

monobasic acid    →   monobazična kiselina

Monobasic acids are acids that have only one replacable hydrogen atom per molecule (HCl, HNO₃).

fatty acid    →   masna kiselina

Fatty acids are aliphatic monocarboxylic acids characterized by a terminal carboxyl group (R-COOH). The higher members of this series of acids occur in nature in the combined form of esters of glycerol (fats), and hence all acids of this family are called fatty acids. Natural fatty acids commonly have a chain of 4 to 28 carbons (usually unbranched and even-numbered), which may be saturated or unsaturated. The most important of saturated fatty acids are butyric (C4), lauric (C12), palmitic (C16), and stearic (C18). The most common unsaturated acids are oleic, linoleic, and linolenic (all C18).

The physical properties of fatty acids are determined by the chain length, degree of unsaturation, and chain branching. Short-chain acids are pungent liquids, soluble in water. As the chain length increases, melting points are raised and water-solubility decreases. Unsaturation and chain branching tend to lower melting points.

muriatic acid    →   murijatična kiselina

Muriatic acid is an obsolete name for hydrochloric acid (HCl). Lavoisier coined the name from the Latin word muria meaning brine.

glutamic acid    →   glutaminska kiselina

Glutamic acid is an electrically charged amino acids. It is one of the two amino acids that contain a carboxylic acid group in its side chains. These acids play important roles as general acids in enzyme active centers, as well as in maintaining the solubility and ionic character of proteins. Glutamic acid is commonly referred to as glutamate, because its carboxylic acid side chain will be deprotonated and thus negatively charged in its anionic form at physiological pH. Glutamic acid is referred to as a non-essential amino acid because a healthy human can synthesize all the glutamic acid needed for normal body function from other amino acids.

• Abbreviations: Glu, E
• IUPAC name: 2-aminopentanedioic acid
• Molecular formula: C₅H₉NO₄
• Molecular weight: 147.13 g/mol

organic acid    →   organska kiselina

Organic acid is an organic compound which is sour, most often these are carboxylic acids (RCOOH).

Schiff base    →   Schiffova baza

Schiff base is a class of compounds derived by the chemical reaction (condensation) of aldehydes or ketones with aromatic amines, for example

They were named after the German chemist Hugo Schiff (1834-1915).

lactic acid    →   mliječna kiselina

Lactic acid is an acid produced as a result of anaerobic respiration in muscles and red blood cells, i.e. when glycogen is used as an energy source for respiration rather than oxygen. After production, it is converted back to glycogen in the liver. The build up of large amounts of lactic acid in the blood can lead to stress and toxic effects. High levels are usually a result of sustained, excessive exercise.

theory    →   teorija

Theories are logical explanations or models which are formulated to explain an experimental data. To become established, a theory must be experimentally tested by many different investigators. Theories can usually be not proven; a single contrary experiment can disprove a theory.

valence bond theory    →   teorija valentne veze

Valence bond theory is a theory that explains the shapes of molecules in terms of overlaps between half-filled atomic orbitals, or half filled hybridised orbitals.

lead-acid battery    →   olovni akumulator

Lead-acid battery is a electrical storage device that uses a reversible chemical reaction to store energy. It was invented in 1859 by French physicist Gaston Planté. Lead-acid batteries are composed of a lead(IV) oxide cathode, a sponge metallic lead anode and a sulphuric acid solution electrolyte.

In charging, the electrical energy supplied to the battery is changed to chemical energy and stored. The chemical reaction during recharge is normally written:

In discharging, the chemical energy stored in the battery is changed to electrical energy. During discharge, lead sulfate (PbSO4) is formed on both the positive and negative plates. The chemical reaction during discharge is normally written:

Lead acid batteries are low cost, robust, tolerant to abuse, tried and tested. For higher power applications with intermittent loads however, they are generally too big and heavy and they suffer from a shorter cycle life.