CHEMISTRY GLOSSARY
manganometry → manganometrija
Manganometry is a quantitative oxidimetric method based on measurement of potassium permanganate (KMnO4) spent for an oxidation of the matter in question.
Daniell cell → Daniellov članak
In 1836 the British chemist John Frederic Daniell (1790-1845) proposed an improved electric cell that supplied an even current during continuous operation. Daniell cell consisted of a glass jar containing copper and zinc electrodes, each immersed in their respective acidic sulphate solutions. The two solutions were separated by a porous clay cylinder separator. It was a galvanic cell in which the spontaneous electrodissolution of zinc and electroplating of copper provided the electrical current.
Zn(s) |
→ | Zn2+ + 2e- |
+0.763 V |
Cu2+ + 2e- |
→ | Cu(s) |
+0.337 V |
Zn(s) + Cu2+ |
→← | Zn2+ + Cu(s) |
+1.100 V |
dropping mercury electrode → kapajuća živina elektroda
Dropping mercury electrode (DME) is a working electrode arrangement for polarography in which mercury continuously drops from a reservoir through a capillary tube (internal diameter 0.03 - 0.05 mm) into the solution. The optimum interval between drops for most analyses is between 2 and 5 s. The unique advantage to the use of the DME is that the constant renewal of the electrode surface, exposed to the test solution, eliminates the effects of electrode poisoning.
micelle → micele
Micelle is an electrically charged colloidal particle, usually organic in nature, composed of aggregates of large molecules, e.g., in soaps and surfactants. For aqueous solutions, the hydrophilic end of the molecule is on the surface of the micelle, while the hydrophobic end (often a hydrocarbon chain) points toward the centre.
Millon’s reaction → Millonova reakcija
Millon’s reaction is used for testing proteins by the appearance of red colour which the proteins give by reacting with a solution of mercury in nitric acid.
molar absorption coefficient → molarni apsorpcijski koeficijent
Molar absorption coefficient (ε) is the absorption coefficient divided by amount-of-substance concentration of the absorbing material in the sample solution (ε = a/c). The SI unit is m2mol-1. Also called extinction coefficient, but usually in units of dm3cm-1mol-1.
electrical double layer → električni dvosloj
Electrical double layer is the structure of charge accumulation and charge separation that always occurs at the interface when an electrode is immersed into an electrolyte solution. The excess charge on the electrode surface is compensated by an accumulation of excess ions of the opposite charge in the solution. The amount of charge is a function of the electrode potential. This structure behaves essentially as a capacitor. There are several theoretical models that describe the structure of the double layer. The three most commonly used ones are the Helmholtz model, the Gouy-Chapman model, and the Gouy-Chapman-Stern model.
electrode of the first kind → elektroda prvog reda
Electrode of the first kind is a simple metal electrode immersed in a solution containing its own ion (e.g., silver immersed in a silver nitrate solution). The equilibrium potential of this electrode is a function of the concentration (more correctly of activity) of the cation of the electrode metal in the solution (see Nernst’s electrode potential equation).
Nessler’s reagent → Nesslerov reagens
Nessler’s reagent is a solution of mercury(II) iodide (HgI2) in potassium iodide and potassium hydroxide named after the German chemist Julius Nessler (1827-1905). It is used in testing for ammonia, with which it forms a brown coloration or precipitate.
Citing this page:
Generalic, Eni. "Nevodena otopina." Croatian-English Chemistry Dictionary & Glossary. 29 June 2022. KTF-Split. {Date of access}. <https://glossary.periodni.com>.
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