CHEMISTRY GLOSSARY

toxin    →   toksin

Toxins are effective and specific poisons produced by living organisms. They usually consist of an amino acid chain which can vary in molecular weight between a couple of hundred (peptides) and one hundred thousand (proteins). They may also be low-molecular organic compounds. Toxins are produced by numerous organisms, e.g., bacteria, fungi, algae and plants. Many of them are extremely poisonous, with a toxicity that is several orders of magnitude greater than the nerve agents. Botulinum toxin, produced by the bacteria Clostridium botulinum, is the most poisonous substance known.

tryglyceride    →   triglicerid

Triglyceride is an ester of glycerol and three fatty acids. It is the main constituent of vegetable oil and animal fats. The fatty acids attached to the glycerol can be the same or different. Natural fatty acids found in plants and animals are typically composed only of even numbers of carbon atoms (usually from 16 to 20) due to the way they are bio-synthesized from acetyl CoA.

U-tube manometer    →   U-manometar

U-tube manometer contains water or mercury in a U-shaped tube, and is usually used to measure gas pressure. One end of the U tube is exposed to the unknown pressure field (P) and the other end is connected to a reference pressure source (usually atmospheric pressure) (P_ref), shown in the schematic below.

If fluid C is the atmosphere, fluid B is the liquid in the U tube (e.g. water or mercury), and fluid A is a gas, then we can assume that ρB >> ρA, ρC. The pressure contributed by the weight of gas within the U tube can therefore be neglected. The gage pressure of the gas can be approximated by,

water    →   voda

Water (H₂O) (dihydrogen oxide) is a binary compound that occurs at room temperature as a clear colorless odorless tasteless liquid; freezes into ice below 0 °C and boils above 100 °C. Water is a chemical compound which is essential for living organisms and it is widely used as a solvent.

Wohler’s synthesis    →   Wohlerova sinteza

Wöhler’s synthesis is a synthesis of urea performed by the German chemist Friedrich Wöhler (1800-1882) in 1828. He discovered that urea (CO(NH₂)₂) was formed when a solution of ammonium isocyanate (NH₄NCO) was evaporated. At the time it was believed that organic substances such as urea could only be made by living organisms, and its production from an inorganic compound was a notable discovery.