CHEMISTRY GLOSSARY

cation exchange    →   kationski izmjenjivač

Cation exchange is a cationic resin has positive ions built into its structure and therefore exchanges negative ions. In the cation exchange, the side groups are ionised acidic groups, such as (-SO₃H, -COOH, -OH) to which cations H⁺ are attached. The exchange reaction is one in which different cations in the solution displace the H⁺ from the solid.

citrate    →   citrati

Citrate is a salt or ester of citric acid.

conjugated base    →   konjugirana baza

Conjugated base is a particle which is left after a molecule of acid releases a proton.

curium    →   kurij

Curium was discovered by Glenn T. Seaborg, Ralph A. James and Albert Ghiorso (USA) in 1944. Named in honour of Pierre and Marie Curie. It is silvery, malleable, synthetic radioactive metal. So radioactive it glows in the dark. Curium was made by bombarding plutonium with helium ions.

carbohydrate    →   ugljikohidrat

Carbohydrates (often called carbs for short) are polyhydroxy aldehydes or ketones, or substances that yield such compounds on hydrolysis. They are also known as saccharides, a term derived from the Latin word saccharum for sugar. Carbohydrates are the most abundant class of compounds in the biological world, making up more than 50 % of the dry weight of the Earth’s biomass. Every type of food we eat can have its energy traced back to a plant. Plants use carbon dioxide and water to make glucose, a simple sugar, in photosynthesis. Other carbohydrates such as cellulose and starch are made from the glucose. Light from the sun is absorbed by chlorophyll and this is converted to the energy necessary to biosynthesize carbohydrates

The term carbohydrate was applied originally to monosaccharides, in recognition of the fact that their empirical composition can be expressed as C_x(H₂O)_y. Later structural studies revealed that these compounds were not hydrates but the term carbohydrate persists.

Carbohydrates are generally classed as either simple or complex. Simple sugars, or monosaccharides, are carbohydrates that can’t be converted into smaller subunits by hydrolysis. Complex carbohydrates are made of two (disaccharides) or more (oligosaccharides, polysaccharides) simple sugars linked together by acetal (glycosidic) bonds and can be split into the former by hydrolysis.

cerium    →   cerij

Cerium was discovered by Martin Heinrich Klaproth (Germany) and by Jöns Jacob Berzelius (Sweden) in 1803 and Wilhelm von Hisinger (Germany) in 1814. Named after the asteroid Ceres this discovered two years before the element. It is malleable, ductile, iron-grey metal. Tarnishes in air; reacts easily with water. Dissolves in acids; ignites when heated. Metal ignites and burns readily. Strong reductant. Cerium is most abundant rare earth metal. Found in many minerals like monazite sand [Ce(PO₄)]. Its oxides are used in the optics and glass-making industries. Its salts are used in the photography and textile industry. Used in high-intensity carbon lamps and as alloying agents in special metals.

decomposing    →   raščinjavanje

Decomposing in analytical chemistry means that a certain substance is converted, by melting it with a suitable melting medium (sodium carbonate, sodium hydroxide, sodium peroxide, ...) in the kind of compound which will afterwards that dissolve in water, acid or base very easily.

DNA    →   DNK

DNA is abbreviation for deoxyribonucleic acid.

effervescence    →   pjenušanje

Effervescence is the formation of gas bubbles in a liquid by a chemical reaction. An example of effervescence is the release of carbon dioxide which bubbles as a gas from the liquid when limestone chips, which are composed of calcium carbonate, are added to dilute hydrochloric acid.

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.