CHEMISTRY GLOSSARY
fluorescence → fluorescencija
Fluorescence is a luminescence phenomenon in which electron returns to it's ground state almost instantaneously (less than 10-8 second), and in which emission from a luminescent substance ceases when the exciting source is removed. Fluorescence is characterized by radiation emission in all directions.
galvanostat → galvanostat
Galvanostat is an electronic instrument that controls the current through an electrochemical cell at a preset value, as long as the needed cell voltage and current do not exceed the compliance limits of the galvanostat.
Gaussian system of units → Gaussov sustav jedinica
Gaussian system of units is a hybrid system used in electromagnetic theory, which combines features of both the electrostatic cgs subsystem (esu) and electromagnetic cgs subsystem (emu). With three base units, it uses em units in magnetism and es units in electrostatics. This involves using the constant c (the velocity of light in vacuum) to interrelate these sets of units.
covalent bond → kovalentna veza
Covalent bond is a chemical bond between two atoms whose stability results from the sharing of two electrons, one from each atom (H· + ·H = H:H or H-H).
cyclic voltammetry → ciklička voltametrija
Cyclic voltammetry (CV) is an electrochemical measuring technique used for the determination of the kinetics and mechanism of electrode reactions. The potential of the working electrode is controlled (typically with a potentiostat) and the current flowing through the electrode is measured. It is a linear-weep voltammetry with the scan continued in the reverse direction at the end of the first scan. This cycle can be repeated a number of times, and is used for corrosion studies.
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 |
geometrical optics → geometrijska optika
In most cases light can be described as an electromagnetic wave. Geometrical optics is an approximation in which the waves can be represented as straight-line rays. This approximation is valid if the light waves do not meet obstacles comparable in size to the wavelength of radiation.
Heisenberg uncertainty principle → Heisenbergov princip neodređenosti
Heisenberg uncertainty principle is the principle that it is not possible to know with unlimited accuracy both the position and momentum of a particle. The German physicist Werner Heisenberg (1901-1976) discovered this principle in 1927.
dialysis → dijaliza
Dialysis is a method by which large molecules (such as starch or protein) and small molecules (such as glucose or amino acids) may be separated in a solution by selective diffusion through a semipermeable membrane. Through this kind of membrane dissolved particles pass and colloid dimension particles fall behind. For example, if a mixed solution of starch and glucose is placed in a closed container made of a semipermeable substance (such as cellophane), which is then immersed in a beaker of water, the smaller glucose molecules will pass trough the membrane into the water, while the starch molecules remain behind.
diamagnetism → dijamagnetizam
In diamagnetism the magnetisation is in the opposite direction to that of the applied field, i.e. susceptibility is negative. It results from changes induced in the orbits of electrons in the atoms of a substance by the applied field, the direction of the change opposing the applied flux.
Citing this page:
Generalic, Eni. "Valentni elektron." Croatian-English Chemistry Dictionary & Glossary. 29 June 2022. KTF-Split. {Date of access}. <https://glossary.periodni.com>.
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