20.500.12556/RUL-172081 Površinska napetost vodnih raztopin natrijevega klorida in natrijevega acetata Surface tension of aqueous solutions of sodium chloride and sodium acetate Površinska napetost ima pomembno vlogo tako v naravnih kot v tehnoloških procesih. Z dodajanjem elektrolitov jo lahko prilagodimo specifičnim potrebam in s tem izboljšamo učinkovitost aplikacij. Nekoliko manj raziskan je vpliv temperature na površinsko napetost raztopin elektrolitov, ki je prav tako pomemben za njeno razumevanje. V sklopu magistrskega dela smo v laboratorij uvedli nov instrument Tensíío Krüss za merjenje površinske napetosti, ki omogoča meritve tudi manjših količin vzorca (<1 mL) pri različni temperaturah. Z metodo Wilhelmyjeve ploščice smo v temperaturnem območju med 10 °C in 45 °C izvedli meritve z večjim in manjšim volumnom za vodo in za vodne raztopine natrijevega klorida (NaCl) in natrijevega acetata (NaOAc) v koncentracijskem območju ~1 < m/mol kg-1 < ~ 5. Rezultate dobljenih vrednosti za površinsko napetost vode smo primerjali z vrednostmi v literaturi. Za meritve, izvedene z večjim volumnom, so rezultati odstopali do 1 % ter za manjši volumen do 3 %. Zaradi pomanjkanja raziskav na tem področju, smo s podatki iz literature uspeli primerjati samo del naših vrednosti za vodne raztopine NaCl in NaOAc. Izmerili smo tudi gostote raztopin za enako temperaturno območje in s tem preverili koncentracije pripravljenih raztopin. Pri izvedbi meritev površinske napetosti smo se soočili z izzivi termostatiranja, zato imajo rezultati pri skrajnih temperaturah nekoliko večje odstopanje od prave vrednosti. Surface tension plays an important role in both natural and technological processes. By adding electrolytes, we can adjust it to specific needs and improve the efficiency of various applications. The effect of temperature on the surface tension of electrolyte solutions is somewhat less studied, although it is equally important for it’s understanding. As part of this master's thesis, we introduced a new instrument for measuring surface tension, the Tensíío Krüss. This instrument allows measurements of small sample volumes (<1 mL) at different temperatures. Using the Wilhelmy plate method, we measured surface tension between 10 °C and 45 °C for both large and small sample volumes. Measurements were performed on water, as well as aqueous solutions of sodium chloride (NaCl) and sodium acetate (NaOAc) in the concentration range of ~1 < m/mol kg-1 < ~ 5. We compared our surface tension measurements for water with values from the literature. For larger sample volumes, our results deviated by up to 1%, and for smaller volumes, up to 3%. Due to limited data available in the literature, we were only able to compare part of our results for NaCl and NaOAc solutions. We also measured the density of the solutions across the same temperature range to verify the concentrations of our prepared samples. During the surface tension measurements, we encountered challenges with temperature control, so the results at the lowest and highest temperatures show slightly higher deviations from the expected values. površinska napetost tenziometer elektroliti termodinamika surface tension tensiometer electrolytes thermodynamics true false false Slovenski jezik Angleški jezik Magistrsko delo/naloga 2025-09-05 10:40:06 2025-09-05 10:40:12 2025-10-24 10:39:44 0000-00-00 00:00:00 2025 0 0 0000-00-00 NiDoloceno NiDoloceno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 25357 254619907 Vidmar_Tine_-_Povrsinska_napetost_vodnih_raztopin_natrijevega_klorida_in_natrijevega_acetata.pdf Vidmar_Tine_-_Povrsinska_napetost_vodnih_raztopin_natrijevega_klorida_in_natrijevega_acetata.pdf 1 6B4B84198DE1866192F45515897EFBA8 2dae7ebbd6ebb951099b8fd94dba18bcced4ef9dfedd0012bc315a5bd734fb76 c963944f-8a33-11f0-9328-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=215817 Fakulteta za kemijo in kemijsko tehnologijo 0 0 0