Effect of Project Based Learning on Academic Achievement of Chemistry Teacher Candidates in the Application of Spectroscopic Analysis Method

Bu çalışmada, Analitik Kimya laboratuvar dersi “Işık-madde etkileşimine dayanan UV/Görünür bölge spektroskopik analiz yöntemi uygulamaları” konusunda, proje tabanlı öğrenme yaklaşımının öğrencilerin akademik başarılarına etkisi incelenmiştir. Araştırmada, ön ve son test kontrol gruplu yarı deneysel desen kullanılmıştır. Konu, deney grubunda proje tabanlı öğrenme yaklaşımı ile kontrol grubunda ise öğretim programına uygun şekilde yürütülmüştür. Son test akademik başarı puanlarının Mann-Whitney U Testi analizi sonuçlarına göre; öğrencilerin akademik başarılarında proje tabanlı öğrenme yaklaşımının kullanıldığı deney grubu lehine anlamlı bir fark olduğu gözlenmiştir (p<.05). Wilcoxon işaretli sıralar testi sonuçları; deney ve kontrol gruplarının her ikisinde de grup içi akademik başarı puanlarında artış olduğunu göstermiştir. Cohen’s d değerine göre, deney grubunda uygulanan öğrenme yaklaşımının büyük etki değerine sahip olduğu söylenebilir (d=0,88). Yarı yapılandırılmış görüşmelerin içerik analizinden elde edilen sonuçlar, deney grubu öğrencilerinin konunun uygulanan öğrenme yaklaşımı ile işlenmesini daha akılda kalıcı bulduklarını göstermiştir.In this work, the effect of project based learning approach on students’ academic achievement on the topic of “Application of UV/Visible spectroscopic analysis method based on light-matter interaction” in Analytical Chemistry Laboratory lesson. Pre- and post-test quasi experimental design with control group was applied in this research. In the experimental group, the subject was carried out with the project based learning approach and in the control group in accordance with the teaching program. It was observed that there was a significant difference in the students’ academic achievement in favour of the experimental group in which the project based learning approach was used according to the Mann-Whitney U test analysis results of the post-test academic achievement scores (p<.05). Wilcoxon signed rank test results showed that the increase of students’ academic achievement of within both groups. It can be also stated that project based learning approach has a great effect size considering to Cohen’s d value (d=0.88). Content analysis of semistructured interview results demonstrated that the experimental group students find it more memorable to process the subject with an applied approach

Voltammetric Determination of Epinephrine in Pharmaceutical Sample with a Tyrosinase Nanobiosensor

A novel carbon paste electrode modified with a multiwalled carbon nanotube (MWCNT), tyrosinase, and Nafion membrane (CP/MWCNT/Tyr/Nafion) was developed for voltammetric determination of epinephrine (EP). The CP/MWCNT/Tyr/Nafion biosensor exhibited linear dynamic range from 5.0×10-6 M to 5.0×10-4 M EP concentration with a good correlation coefficient (R2=0.9985). The detection limit of the biosensor was calculated as 3.0×10-7 M EP from the signal-to-noise ratio (S/N = 3). Reproducibility of the biosensor was also calculated from relative standard deviation as 3.8% (n=5). Ascorbic acid (AA) and uric acid (UA) did not interfere in the quantification of epinephrine. The developed biosensor was also successfully applied for the determination of epinephrine in pharmaceutical sample. The CP/MWCNT/Tyr/Nafion biosensor has good sensitivity, selectivity, stability, easy preparation procedure, and short analysis time and can be used for the determination of EP in pharmacological samples

The effects of problem-based learning (PBL) on the academic achievement of students studying 'Electrochemistry'

This study investigates the effects of problem-based learning (PBL) on students' academic achievements in studying 'Electrochemistry' within a course on Analytical Chemistry. The research was of a pretest-posttest control group quasi-experimental design and it was conducted with second year students in the Chemistry Teaching Program at the Faculty of Education at Dokuz Eylul University. The topic was taught with PBL in the experimental group and with expository teaching strategies in the control group. The 'Chemistry achievement test (CAT)' was applied as the pre-test and post-test in both groups. Post-test scores from the CAT demonstrated that there was a significant difference between the academic achievements of the two groups in favour of the experimental group (U = 8.500, p < 0.05). After using PBL for a period, eleven open-ended questions related to the topic were asked to both groups. The results of these questions were categorized and the scores obtained from the categories were evaluated using content analysis. The results of the scores obtained from the open-ended questions showed that the students in the experimental group were able to make statements containing fewer misconceptions and also had a better understanding of this topic when compared to the students in the control group (U = 2.500, p < 0.05). The correlation between the scores in the CAT post-test and the scores obtained from the open-ended questions of the experimental and control groups was also examined. The Spearman correlation coefficients were found to be 0.907 and 0.595 for the experimental and the control group, respectively. This finding indicated that there was a positive and very high level of statistically significant correlation between the scores in the CAT post-test and the scores obtained from the open-ended questions of the students in the experimental group. Therefore this finding also supports the conclusion that the students in the experimental group were better able to understand the topic and its structure compared to the students in the control group. At the end of the application, the results of semi-structured interviews carried out showed that students in the experimental group had positive opinions regarding PBL

Analitik Kimya Laboratuar Uygulamasında Örnek-Olaya Dayalı Öğrenmenin Kullanıldığı Bir Materyal Geliştirilmesi ve Öğrenci Görüşleri

The objective of this study is to investigate students’ views about the case study and case-based learning (CBL). The case study is prepared concerning the complex formation titration based on ethylene diamine tetra acetic acid compound (EDTA) and complex formation reaction of metal ions and the experiment of hardness determination in water in the Analytical Chemistry Laboratory course. The sample of this descriptive study consists of 2nd, 4th and 5th grade student teachers (N=23) (ages between 20-23 years-old) studying in the department of Chemistry Teaching at a university in Izmir. ‘Structured Interview Form’ was used as data collection tool. The data were analyzed via content analysis, which is a qualitative analysis technique. According to the data obtained; the students stated that the CBL method was comprehensible and convenient. In addition, they had also positive views that the case study being prepared was an entertaining study building up the desire for investigation and motivation.Bu çalışmanın amacı, örnek olay ve örnek-olaya dayalı öğrenmeye ilişkin öğrenci görüşlerini araştırmaktır. Örnek olay, Analitik Kimya Laboratuarı dersi suların sertliğinin belirlenmesi deneyinde etilen diamin tetra asetik asit bileşiği (EDTA) ile metal iyonlarının kompleks oluşum reaksiyonlarına dayalı kompleks oluşum titrasyonuyla ilgili olarak hazırlanmıştır. Bu betimleyici çalışmanın örneklemi, İzmir’de bir üniversitede Kimya Öğretmenliği bölümünde okuyan ikinci, dördüncü ve beşinci sınıf öğretmen adaylarından (N=23) (20–23 yaşlar arasında) oluşmuştur. ‘Yapılandırılmış Görüşme Formu’ veri toplama aracı olarak kullanılmıştır. Veriler, nitel analiz tekniklerinden içerik analiziyle analiz edilmiştir. Elde edilen verilere göre; öğrenciler örnek-olaya dayalı öğrenme yönteminin kapsamlı ve uygun olduğunu belirtmişlerdir. Ayrıca hazırlanan örnek olayın araştırma yapma isteklerini ve motivasyonlarını arttırarak öğrenmelerini eğlenceli hale getirdiğine dair olumlu görüşlerde de bulunmuşlardır

Analitik Kimya Laboratuar Uygulamasında Örnek-Olaya Dayalı Öğrenmenin Kullanıldığı Bir Materyal Geliştirilmesi ve Öğrenci Görüşleri

The objective of this study is to investigate students’ views about the case study and case-based learning (CBL). The case study is prepared concerning the complex formation titration based on ethylene diamine tetra acetic acid compound (EDTA) and complex formation reaction of metal ions and the experiment of hardness determination in water in the Analytical Chemistry Laboratory course. The sample of this descriptive study consists of 2nd, 4th and 5th grade student teachers (N=23) (ages between 20-23 years-old) studying in the department of Chemistry Teaching at a university in Izmir. ‘Structured Interview Form’ was used as data collection tool. The data were analyzed via content analysis, which is a qualitative analysis technique. According to the data obtained; the students stated that the CBL method was comprehensible and convenient. In addition, they had also positive views that the case study being prepared was an entertaining study building up the desire for investigation and motivation.Bu çalışmanın amacı, örnek olay ve örnek-olaya dayalı öğrenmeye ilişkin öğrenci görüşlerini araştırmaktır. Örnek olay, Analitik Kimya Laboratuarı dersi suların sertliğinin belirlenmesi deneyinde etilen diamin tetra asetik asit bileşiği (EDTA) ile metal iyonlarının kompleks oluşum reaksiyonlarına dayalı kompleks oluşum titrasyonuyla ilgili olarak hazırlanmıştır. Bu betimleyici çalışmanın örneklemi, İzmir’de bir üniversitede Kimya Öğretmenliği bölümünde okuyan ikinci, dördüncü ve beşinci sınıf öğretmen adaylarından (N=23) (20–23 yaşlar arasında) oluşmuştur. ‘Yapılandırılmış Görüşme Formu’ veri toplama aracı olarak kullanılmıştır. Veriler, nitel analiz tekniklerinden içerik analiziyle analiz edilmiştir. Elde edilen verilere göre; öğrenciler örnek-olaya dayalı öğrenme yönteminin kapsamlı ve uygun olduğunu belirtmişlerdir. Ayrıca hazırlanan örnek olayın araştırma yapma isteklerini ve motivasyonlarını arttırarak öğrenmelerini eğlenceli hale getirdiğine dair olumlu görüşlerde de bulunmuşlardır