Naslov
SIGNIFICANCE OF EXPERIMENT IN THE TEACHING PROCESS – APPLICATION OF POTENTIOMETRIC EXPERIMENT AS EXAMPLE

Autori
Tomaš, Renato ; Vladušić, Roko

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
PROCEEDINGS BOOK / Yamamura, Akihiro - Dubai : Sakarya University, 2016, 632-632

Skup
International Educational Technology Conference

Mjesto i datum
Dubai, Ujedinjeni Arapski Emirati, 04.02.2016. - 06.02.2016

Vrsta sudjelovanja
Predavanje

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
education; ionic solutions; potentiometric experiment; teaching process

Sažetak
Experiment is a vital part of chemistry education. The improvement in teaching experiments are an important way to raise the quality of chemistry teaching: they give students the opportunity to perform experiments and data analysis independently, and their interest in science can be stimulated (Hofstein, 2004.). We present an interesting example of a potentiometric experiment for determination of transference numbers (Tomaš et al., 2013.) which is used in our course of Physical Chemistry of Electrolyte Solutions for graduate students of chemistry at the Faculty of Chemistry and Technology, University of Split. Students perform a potentiometric experiment using specially designed transference number cell (Braun & Weingärtner, 1985). Furthermore, using data of the mean activity coefficients available in the literature for NaCl in water at 25C, they can calculate potential difference (E) of the corresponding cell without transference, using Nernst equation. Finally, transference number (t) of sodium ion constituent can be determined as dEtransfer/dE. Extrapolation of the polynomial function, i.e. t = f(m) to zero molality gives the limiting transference number. If combining experimental values for limiting molar conductivity of NaCl they can calculate limiting ionic conductivities. Through these activities, many educational goals were achieved: students became well trained in scientific methods and their abilities to analyse and solve problems related to ionic solutions (such as degree of ion association and ion-solvent interaction) improved. More specifically, it seems that students easily connected how changes in temperature or in solvent nature affected its physical properties (such as viscosity and dielectric constant), if they have the opportunity to examine the influence some of these parameters during the experiment(s). The results encourage us to take our research into new phase in which we will investigate, by interview method, the impact of these experiments on the student’s deep understanding of ion association and ion-solvent interaction.

Izvorni jezik
Engleski

Znanstvena područja
Kemija

Napomena
Video presentation

POVEZANOST RADA