Understanding the concept of chemistry can not only be done directly by studying chemistry, but even chemistry will also be more easily understood if contextualized with culture, because the concept of chemistry is very analogous to culture (Ethnochemistry). This paper will discuss Ethnochemistry in the local wisdom of the Sasak tribe, West Nusa Tenggara, Indonesia contained in the Merarik (wedding) tradition. In this tradition, there are social, moral and spiritual values such as the concept of giving and receiving, cooperation, mutual respect, and the concept of a mutual need to achieve stability. These concepts have very strong relevance to the theory of chemical bonds which includes the concept of electron stability, electron configuration, positive and negative ions, and the theory of chemical bond formation so that it can be concluded the theory of chemical bonds has interconnection with local wisdom of Sasak tribe (Ethnochemistry). The concept of material and its changes integrated into local Sasak wisdom are reflected in the use of chemical elements from various types of metals such as gold, silver, bronze, copper, brass, and various other metals for the manufacture of traditional ceremonial tools and traditional Sasak arts. Likewise, the concept of material change is found in food processing, traditional art tools and cultural products of the Sasak tribe. Thus the application of ethnhochemistry in chemistry learning can act as a natural laboratory & learning media so as to make chemistry learning more enjoyable and relevant to students' daily lives (contextual-based learning).

The powder complex of tris(phenanthroline)cobalt(II) trifluoroacetate (TFA) has been prepared by interaction of cobalt(II) nitrate, phenanthroline (phen) in aqueous solution with drops of ethanol, and an excess of saturated aqueous solution of sodium trifluoroacetate, whereupon the yellowish powder was produced. AAS measurment for the metal content, equivalent conductance (1:2), and TGA-DTA of the powder suggest the corresponding formula of [Co(phen)3](TFA)2.5H2O. The efffective magnetic moment of 4.9 BM indicates the high-spin nature of this complex which corresponds to three unpaired electrons in the electronic configuration of Co(II) with significantly higher than the spin only value due to the orbital contribution. UV-Vis spectrum of the complex reveals the d-d spin-allowed transition bands as well as the MLCT and intraligand band. The estimating transition energy ratio of 2.04 for ν2/ν1, is clearly in the range for octahedral configuration. The infrared spectral property indicates the main mode of vibrations for the functional groups of ligand phen and TFA, and thus supports strongly the formula proposed for this complex. The corresponding powder XRD was then refined using Rietica-Le Bail method and found to be fit as triclinic crystal system with space group of PĪ.

This study aims to determine the effect of a macromedia flash-based guided inquiry model on students’ critical thinking skill and self-regulated learning. This study was a quasi-experiment, with a post-test only group design. The subjects were 96 eleventh-graders of divided into two groups. Fifty students in the experimental group used macromedia flash-based guided inquiry model and 46 students in the control group used direct instruction model. Data collection techniques were a test of critical thinking skill consisting seven essay questions to see students’ critical thinking skill and a questionnaire of self-regulated learning consisting 33 statements to see students’ self-regulated learning. The data were analyzed using MANOVA. The results showed that students taught with macromedia flash-based guided inquiry model have a statistically difference on their critical thinking skill and self-regulated learning at significance level 0.05 while students taught with direct instruction model showed critical thinking at lower level. In conclusion, a macromedia flash-based guided inquiry model can improve students’ critical thinking skill and students’ self-regulated learning.

The objective of this research was to investigate the level of students' attitudes toward Chemistry and Learning Experience (ATCLE). The research sample included 191 students (61 male and 130 female) from three universities; Universitas Negeri Mataram, Universitas Islam Negeri Mataram, and IK1P Mataram, Indonesia. The sample has been selected through cluster random sampling and snowballs random sampling. Mixed method research with a descriptive correlational survey model and a semi-structured interview was employed for the study. The data were collected by Chemistry Attitudes and Experiences Questionnaire (CAEQ) and an interview guide. Results showed no significant correlation in the level of attitude toward chemistry based on gender and grades. The finding also revealed that the attitude of pre-service chemistry teachers based on gender and grade were more positive towards research in chemistry than jobs related to chemistry. However, grades influenced the students learning experience, but there was no influence of gender on students learning experience. It is suggested that teachers need to develop a positive attitude toward chemistry and learning experiences of the students through inquiry-based learning practices.

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The complex containing Ni(II)-2,2’-bipyridin (bipy)-trifluoroacetate (TFA) was prepared by direct interaction of the corresponding precursors in an aqueous solution. AAS measurement for metal content, TGA-DTA analysis and electrical conductance suggest the ionic complex of [Ni(bipy)3](CF3COO)2·6H2O. The magnetic moment of 3.13–3.17 BM indicates the paramagnetism corresponding to two unpaired electrons which is clearly higher than that of the spin only value (2.87 BM), and commonly observed due to the spin-orbit coupling in Ni(II). UV-Vis spectral property revealed the first two main ligand field bands centered at about 14200 and 18650 cm–1, which are attributed to the spin-allowed transition, 3A2g→3T2g and 3A2g→3T1g(F), respectively. The expected third band at higher energy seems to appear as a shoulder at 26500 cm–1 (378 nm), as it is masked by a strong intensity of charge transfer band centered at 31050 cm–1. The infrared spectrum exhibits mode of vibrations of the functional groups of ligand and TFA. The powder diffractogram was refined by Le Bail method and found fit as monoclinic system of space group of P21/M, with figures of merit: Rp = 3.62, Rwp = 5.76, Rexp = 3.48, goodness of fitting (GOF) 2.745 and the derived Bragg R-Factor = 0.05.

Education is currently facing the challenges of 21st-century learning. Moreover, covid-19 pandemic has caused all face-to-face learning activities in schools to be replaced with online learning. This phenomenon requires teachers to understand and have competency in technological, pedagogical and content knowledge (TPACK). The aim of this research is to describe the perceptions of TPACK high school chemistry teachers. This research was conducted on 32 chemistry teachers in the province of East Nusa Tenggara using the TPACK questionnaire instrument with seven components. TPACK perception data were analyzed using a descriptive quantitative approach, while the difference in teacher TPACK based on gender and teaching experience was analyzed using the Mann-Whitney U test with SPSS.25 because the sample was small. In accordance with the data analysis carried out states that the chemistry teacher's perception of TPACK is in the "good" category in general and the highest average score is in the PK component. The components that have a strong positive correlation are PK, TPK, TCK, and TPCK which have a significant effect on the perception of TPACK for SMA chemistry teachers. Also, based on gender and teaching experience did not have a significant effect on TPACK perception.

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