CHEMISTRY GLOSSARY

freon    →   freon

Freon (chlorofluorocarbon, CFC) a type of compound in which some or all of the hydrogen atoms of hydrocarbon (usually an alkane) have been replaced by chlorine and fluorine atoms. Most CFC are chemically uncreative and are stable at high temperatures. They are used as aerosol propellants, refrigerants, and solvents, and in the manufacture of rigid packaging foam. CFC because of their chemical inertness, can diffuse unchanged into the upper atmosphere. Here, photochemical reactions cause them to break down and react with ozone. For his reason, their use has been discouraged.

fructose    →   fruktoza

Fructose (fruit sugar) is a ketohexose (a six-carbon ketonic sugar), which occurs in sweet fruits and honey. Glucose and fructose have the same molecular formula, C₆H₁₂O₆, but have different structures. Pure, dry fructose is a very sweet, white, odorless, crystalline solid. Fructose is one of the sweetest of all sugars and is combined with glucose to make sucrose, or common table sugar. An older common name for fructose is levulose, after its levorotatory property of rotating plane polarized light to the left (in contrast to glucose which is dextrorotatory). The polysaccharide inulin is a polymer of fructose.

fullerene    →   fuleren

Fullerene (Buckminsterfullerene) is a form of carbon consisting of 60 carbon atoms bound together to make a roughly spherical "buckyball" (which looks rather like a soccer ball).

substitution    →   supstitucija

Substitution (substitution reaction) is a reaction in which an atom or fragment within a molecule is replaced with another atom or a fragment.

surface tension    →   površinska napetost

Surface tension (σ) is a property of liquids arising from unbalanced molecular cohesive forces at or near the surface, as a result of which the surface tends to contract and has properties resembling those of a stretched elastic membrane. As a result of which the surface tends to contract and has properties resembling those of a stretched elastic membrane.

symmetry    →   simetrija

Symmetry is the property of a molecule, whereby the molecule has the same observed physical structure and appearance, when viewed from different orientations in space.

temperature    →   temperatura

Temperature is a measure to the average kinetic energy of its molecules. The SI unit in which thermodynamic temperature is expressed is the kelvin (K).

terminal    →   terminalni

Terminal in chemistry means: the end of a polymer molecule and a point at which electron connections can easily be made or broken.

gasoline    →   motorni benzin

Gasoline is a complex mixture of volatile hydrocarbons that may have between 5 to 12 carbons. The major components are branched-chain paraffins, cycloparaffins, and aromatics. Gasoline is most often produced by the fractional distillation of crude oil as the fraction of hydrocarbons in petroleum boiling between 30 °C and 200 °C. The quality of a fuel is measured with its octane number. Octane number is the measure of the resistance of gasoline against detonation or preignition of the fuel in the engine. The higher the octane number, the more compression the fuel can withstand before detonating. The octane number is determined by comparing the characteristics of a gasoline to isooctane with good knocking properties (octane number of 100) and heptane with bad (octane number of 0).

glucose    →   glukoza

Glucose (grape sugar, blood sugar), C₆H₁₂O₆, is an aldohexose (a monosaccharide sugar having six carbon atoms and an aldehyde group). An older common name for glucose is dextrose, after its dextrorotatory property of rotating plane polarized light to the right. Glucose in free (in sweet fruits and honey) or combined form (sucrose, starch, cellulose, glycogen) is is probably the most abundant organic compound in nature. During the photosynthesis process, plants use energy from the sun, water from the soil and carbon dioxide gas from the air to make glucose. In cellular respiration, glucose is ultimately broken down to yield carbon dioxide and water, and the energy from this process is stored as ATP molecules (36 molecules of ATP across all processes).

Naturally occurring glucose is D isomers (OH group on the stereogenic carbon farthest from the aldehyde group, C-5, is to the right in the Fischer projection). Although often displayed as an open chain structure, glucose and most common sugars exist as ring structures. In the α form, the hydroxyl group attached to C-1 and the CH₂OH attached to C-5 are located on opposite sides of the ring. β-glucose has these two groups on the same side of the ring. The full names for these two anomers of glucose are α-D-glucopyranose and β-D-glucopyranose.