CHEMISTRY GLOSSARY

calorimetry    →   kalorimetrija

Calorimetry is a measurement of the amount of heat evolved or absorbed in a chemical reaction, change of state, or formation of a solution, or any other event that includes heat transfer.

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:

carbon dating    →   određivanje starosti radioaktivnim ugljikom

Carbon dating is used to the time passed since a living organism died. It is based on measuring the quantity of isotope of carbon-14 that is contained in all living organisms.

chemical property    →   kemijsko svojstvo

Chemical property is a property observed when a substance undergoes a transformation into one or more new substances. Measurement of a chemical property involves a chemical change. For example, determining the flammability of petrol involves burning it, producing carbon dioxide and water.

colorimeter    →   kolorimetar

Colorimeter is an instrument used to measure the strength of colorification in a solution.

colorimetry    →   kolorimetrija

Colorimetry is a quantitative chemical analysis by colour using a colorimeter.

conductivity    →   vodljivost

Conductivity is a measure of the ability of a material to conduct electric current.

conversion factor    →   konverzijski faktor

Conversion factor is a fraction that relates one unit to another. Multiplying a measurement by a conversion factor changes the units of the measurement, for example

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

atmosphere    →   atmosfera

1. Atmosphere is the column of air which is extending several hundred kilometers above the surface the Earth's surface. The density of this air decreases as you proceed up from the surface. The air in the atmosphere consists of 78 % nitrogen, 21 % oxygen, and 0.9 % argon. The remaining 0.1 % of the atmosphere consists of ozone, water vapor, carbon dioxide, methane, helium, and neon. The atmosphere is divided into different regions. The lowest two layers are the troposphere (the layer closest to the earth) and the stratosphere respectively. These two layers contain more than 99 % of the atmospheric molecules.

2. Standard atmosphere (atm) is an obsolete pressure and stress unit which should be discontinued. It is unit of pressure equal to the air pressure measured at mean sea level.

1 atm = 101 325 Pa

Technical atmosphere (at) is an obsolete MKpS pressure and sttress derived unit.

1 at = 98 066.5 Pa

1 atm = 1.033 227 453 at