Određivanje stvarne gustoće prašaka uz pomoć laboratorijskog posuđa

undergraduate thesis

• Title (english): Determination of true powder density by use of laboratory glassware
• Author: Ema Zekić
• Mentor: Jelena Macan (mentor)
• Committee member: Jelena Macan (predsjednik povjerenstva)
• Committee member: Jasna Prlić Kardum (član povjerenstva)
• Committee member: Davor Dolar (član povjerenstva)
• Granter: University of Zagreb; Faculty of Chemical Engineering and Technology; Zagreb
• Defense date and country: 2023-09-05, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Basic Technical Sciences

Abstract

Cilj ovog rada bio je odrediti gustoću praška sastavljenog od staklenih kuglica modificiranom metodom piknometra. Budući da tekućinski piknometar ima jako usko grlo, nepraktičan je za rad s praškastim uzorcima te je u ovom radu gustoća staklenih kuglica određena korištenjem staklene bočice sa čepom i menzure od 10 mL kao improviziranih piknometara. Kao otapalo korišteni su destilirana voda i etanol, a gustoća staklenih kuglica određena je kao aritmetička sredina tri uzastopna mjerenja. Rezultati dobiveni korištenjem staklene bočice i vode kao otapala te korištenjem menzure i oba otapala odgovaraju teorijskoj vrijednosti gustoće od
2,5 g/cm^3. Pritom je najniža standardna devijacija od 0,1823 dobivena korištenjem menzure i vode kao otapala što je i očekivano budući da je menzura graduirano laboratorijsko posuđe za razliku od staklene bočice na kojoj je oznaka proizvoljno urezana dijamantnim nožićem. Na temelju dobivenih rezultata proizlazi da je predstavljena metoda određivanja gustoće staklenih kuglica pomoću improviziranog piknometra pouzdana i dobra alternativa klasičnom piknometru.

Abstract (english)

The purpose of this work was to determine the density of powder consisting of glass beads using a modified pycnometer method. Since the liquid pycnometer has a very narrow neck, it is impractical for working with powder samples. Therefore in this work the density of glass beads was determined using a glass vial with a stopper and a 10 mL graduated cylinder as improvised pycnometers. Distilled water and ethanol were used as solvents, and the density of glass beads was determined as the arithmetic mean of three consecutive measurements. The results obtained using the glass vial and water as solvent and using the graduated cylinder and both solvents correspond to the theoretical density value of 2,5 g/cm^3.
At the same time, the lowest standard deviation of 0,1823 was obtained using the graduated cylinder and water as solvent, which is expected since the cylinder is a graduated laboratory vessel, unlike the glass vial on which a mark is arbitrarily engraved with a diamond knife. Based on the obtained results, the presented method of determining the density of glass balls using an improvised pycnometer is a reliable and good alternative to the classic pycnometer.

• Keywords: gustoća; improvizirani piknometar; prašak; staklene kuglice
• Keywords (english): density; improvised pycnometer; powder; glass beads
• Language: croatian
• URN:NBN: urn:nbn:hr:149:817680
• Study programme: Title: Applied Chemistry - Undergraduate study; specializations in: Environmental chemistry and green technologies, Advanced materials and technologies, Applied organic chemistry; Course: Advanced materials and technologies; Study programme type: university; Study level: undergraduate; Academic / professional title: sveučilišni/a prvostupnik/prvostupnica (baccalaureus/baccalaurea) primijenjene kemije (sveučilišni/a prvostupnik/prvostupnica (baccalaureus/baccalaurea) primijenjene kemije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2023-09-07 07:08:14