CHEMISTRY GLOSSARY

binary    →   binaran

Binary, describing a compound or alloy formed from two elements

chain    →   lanac

Chain is a linear combination of the same type of atom in a molecule. In straight chain molecules, the atoms are arranged in a line, with each atom in the chain linked to one preceding atom and one succeeding atom of the same type. A closed chain molecule is a chain where the atoms are linked in a ring structure.

chelating agent    →   kelatni agens

Chelating agent is ligand that binds to a metal using more than one atom; a polydentate ligand.

chemical reaction    →   kemijska reakcija

Chemical reaction is a change of chemical properties of substances which react with each other. By means of a chemical reaction new substances are created by bond breaking between atoms and molecules of reactants and their reuniting in a new way, thereby creating products. Chemical reactions can be shown by chemical equations.

angular velocity    →   kutna brzina

A point-like object that undergoes circular motion changes its angular position from initial Θ_i to final Θ_f, relative to a fixed axis, specified in a coordinate system with an origin that coincides the centre of the circular path of object. The change in its angular position is called angular displacement ΔΘ = Θ_f - Θ_i. Also, a rigid body that rotates about a specified rotation axis, changing its angular position from initial Θ_i to final Θ_f, undergoes an angular displacement ΔΘ.

The average angular velocity, ω_av, is the ratio of the angular displacement and the time interval Δt=t_f-t_i, in which that displacement occurs.

Θ_f and Θ_i are the initial and final angular position, respectively.

The instantaneous angular velocity ω is the limit of the average angular velocity, as Δt is made to approach zero.

ω_av and ω are positive for the counterclockwise rotation (in direction of increasing Θ) and negative for the clockwise rotation (in direction of decreasing Θ).

SI unit for angular velocity is s^-1.The measure for the angle Θ is radian. The relationship between radians and degrees is:

For example, the angular velocity of the minute hand of a clock is:

chemisorption    →   kemisorpcija

Chemisorption is a binding of a liquid or gas on the surface or in the interior of a solid by chemical bonds or forces.

collagen    →   kolagen

Collagen is a polypeptide substance comprising about one third of the total protein in mammalian organisms. It is the main constituent of skin. Collagen is the primary organic constituent of bone, cartilage, and connective tissue (becomes gelatine through boiling).

complex    →   kompleks

Complex or coordination compound is formed when metal ion (central ion) reacts with molecules or ions which have free electron pairs (ligand). Metal ion and ligand are bonded with a polar covalent bond in which both electrons are given by the ligand.

asparagine    →   asparagin

Asparagine is neutral amino acids with polar side chains. The polar amino acids are an important class of amino acids since they provide many of the functional groups found in proteins. Asparagine is a common site for attachment of carbohydrates in glycoproteins. In general this is not very reactive residues. Asparagine is amide derivative of aspartic acid. Asparagine is not essential for humans, which means that it can be synthesized from central metabolic pathway intermediates and is not required in the diet.

• Abbreviations: Asn, N
• IUPAC name: 2,4-diamino-4-oxobutanoic acid
• Molecular formula: C₄H₈N₂O₃
• Molecular weight: 132.12 g/mol

atom radius    →   radijus atoma

Atoms and molecules have no strict boundaries. The volume of a free atom is usually defined as that volume that contains 90 % of electron cloud. The radius of an atom represents half of interatom distance of two identical atoms which are in touch but are not interconnected either by a covalent or an ionic bond, but with a very weak van der Waals’s bond.