CHEMISTRY GLOSSARY

diamagnetic    →   dijamagnetik

Diamagnetic materials are very weakly repelled by magnetic fields. The atoms or molecules of diamagnetic materials contain no unpaired spins.

disproportionation    →   disproporcioniranje

Disproportionation is a reaction in which the same molecule reduces and oxidates itself at the same time.

elementary reaction    →   elementarna reakcija

Elementary reaction is a reaction that occurs in a single step. Equations for elementary reactions show the actual molecules, atoms, and ions that react on a molecular level.

cellulose    →   celuloza

Cellulose, (C₆H₁₀O₅)_n, is a polysaccharide that consists of a long unbranched chain of glucose units linked by (1→4)-β-glycoside bonds. Nature uses cellulose primarily as a structural material to impart strength and rigidity to plants. Leaves, grasses, and cotton are primarily cellulose. The fibrous nature of extracted cellulose has led to its use in textile industry for the production of cotton, artificial silk, etc. Cellulose also serves as raw material for the manufacture of cellulose acetate, known commercially as acetate rayon, and cellulose nitrate, known as guncotton. Gunncotton is the major ingredient in smokeless powder, the explosive propellant used in artillery shells and in ammunition for firearms.

chain reaction    →   lančana reakcija

Chain reaction is a reaction done in three steps: initiation in which usually radicals are made which react with other molecules in stage of propagation and, when all reactants are spent, it ends by termination when all available radicals are completely spent.

Nuclear chain reaction refers to a process in which neutrons released in fission produce an additional fission in at least one further nucleus. Nuclear power plants operate by precisely controlling the rate at which nuclear reactions occur. On the other hand, nuclear weapons are specifically engineered to produce a reaction that is so fast and intense it cannot be controlled after it has started.

chemical compound formula    →   formula kemijskog spoja

Chemical elements are represented by their symbols, and chemical compounds are represented by a group of symbols of those elements from which the compound is composed. That group of symbols, which shows which atoms and in which number relation they are present in certain compound is called a chemical compound formula.

In a formula chemical symbols show which element is present in a certain compound, and its index shows how much of that element there is in a certain compound. From sulphuric acid formula H₂SO₄ we can see that one molecule of sulphuric acid consists of two atoms of hydrogen, one atom of sulphur and four atoms of oxygen.

equivalent weight    →   ekvivalentna masa

Equivalent weight of a substance participating in a neutralization reaction is that mass of substance (molecule, ion, or paired ion) that either reacts with or supplies 1 mol of hydrogen ions in that reaction.

Equivalent weight of a substance participating in an oxidation/reduction reaction is that weight which directly or indirectly produces or consumes 1 mol of electrons.

fermentation    →   fermentacija

Fermentation is a class of biochemical reactions that break down complex organic molecules (such as carbohydrates) into simpler materials (such as ethanol, carbon dioxide, and water). Fermentation reactions are catalyzed by enzymes.

heat    →   toplina

Heat is a form of energy associated with and proportional to molecular motion. It can be transferred from one body to another by radiation, conduction, or convection.

chemical equation    →   kemijska jednadžba

Chemical equation is a way of denoting a chemical reaction using the symbol for the participating particles (atoms, molecules, ions, etc.); for example,

The single arrow is used for an irreversible reaction; double arrows are used for reversible reactions. When reactions involve different phases, it is usual to put the phase in brackets after the symbol.

The numbers a, b, c, and d, showing the relative numbers of molecules reacting, are called the stoichiometric coefficients. The convention is that stoichiometric coefficients are positive for reactants and negative for products. If the sum of the coefficients is zero, the equation is balanced.