The aim of the study was to analyze students' creative thinking skills in implementing multiple representation approach on 'rate of reaction' topic. The one-shot case study research design was conducted with 30-eleventh grade students drawn from a public senior high school in Yogyakarta, Indonesia. The learning process involved in implementing concept attainment models with multiple representation approach (CAM-MRA). There were five lesson sequences including presentation of example and non-example, formulation of example, formulation and analysis of hypothesis, closure and application. In each session, macroscopic, microscopic, symbolic and mathematics representation were employed to illustrate 'rate of reaction' concepts. The data were collected by creative thinking based on multiple representation test (CT-MRT) with 24 items. The results showed that the CAM-MRA facilitated the students' creative thinking skills of 'rate of reaction'. However, the students still had difficulty to show the microscopic representation. This study suggests that multiple representations in chemistry should be emphasized in chemistry learning at senior high school.

The chemical bonding material is a concept that requires visualization. For students to comprehend chemical bonding concepts better, molecular forms must be depicted in the materials. Consequently, a learning module that can show 3D things made from molecular structures is necessary. This study aims to create and evaluate an augmented reality-based learning module on chemical bonds while examining the similarities and differences between students' interests and learning motivation before and after utilizing the augmented reality-based learning modules. The product is designed utilizing a 4-D model, and this study uses a research and development model. A quasi-experimental method and one group pretest and posttest design were used to evaluate the module involving 53 students chosen randomly. A sample of Hotelling's T2 test was used to analyze the student responses to the questionnaire about interest and motivation for learning. Descriptive quantitative analysis was used to analyze the data from the product quality assessment. The results showed that the developed augmented reality-supported chemical bonding learning module was very suited for chemistry learning and that there were variations between pre- and post-usage in student interest and motivation to study simultaneously or separately

Undoped titanium dioxide (TiO2) and a series of chromium(III) doped TiO2 (Cr-doped TiOfig. 12) with various %wt Cr atom were prepared by a reflux technique. The undoped TiO2 and Cr-doped TiO2 of 1.1, 3.9, 4.4 %wt Cr atom have been successfully analyzed both qualitative and quantitative analysis of powder X-ray diffraction (XRD) data. The qualitative analysis was carried out with the identification of phases in all samples by comparison with Crystallography Open Database (COD) and International Centre for Diffraction Data (ICDD), while the quantitative phase analysis was calculated by reference intensity ratio (RIR) and whole-pattern fitting (Rietveld analysis) methods. The undoped TiO2 consist of three phases: anatase, rutile, and brookite. In the 1.1 %wt Cr-doped TiO2 are detected presenting two phases: anatase (major) and rutile (minor). In the 3.9 %wt Cr-doped TiO2 andin the 4.4 %wt Cr-doped TiO2 consist of anatase as major phase, while CrO2 and TiO2-II phases can be detected as minor phases. The undoped TiO2 was refined in the phase, crystal system and space group of anatase (tetragonal, I41/amd), rutile (tetragonal, P42/mnm) and brookite (orthorhombic, Pbca), while the 1.1 %wt Cr-doped TiO2 was refined based on anatase (tetragonal, I41/amd), rutile (tetragonal, P42/mnm). Finally, in the 3.9 %wt Cr-doped TiO2 and 4.4 %wt Cr-doped TiO2,respectively were refined in the crystal system and space group of anatase (tetragonal, I41/amd).

Thin films of SnSe and SnS semiconductors had been prepared by vacuum evaporation techniques. All prepared samples were characterized on their structure, optical, and electrical properties in order to know their application in technology. The crystal structure of SnSe and SnS was determined by X-Ray Diffraction (XRD) instrument. The morphology and chemical composition were obtained by Scanning Electron Microscopy (SEM) coupled with Energy Dispersive of X-Ray Analysis (EDAX). The optical property such as band gap was determined by DR-UV-Vis (Diffuse Reflectance-Ultra Violet-Visible) spectroscopy, while the electrical properties were determined by measuring the conductivity by four probes method.The characterization results indicated that both SnSe and SnS thin films were polycrystalline. SnSe crystallized in an orthorhombic crystal system with the lattice parameters of a = 11.47 Å, b = 4.152 Å and c = 4.439 Å, while SnS had an orthorhombic crystal system with lattice parameters of a = 4.317 Å, b = 11.647 Å and c = 3.981 Å. Band gaps (Eg) of SnSe and SnS were 1.63 eV and 1.35 eV, respectively. Chemical compositions of both thin films were non-stoichiometric. Molar ratio of Sn : S was close to ideal which was 1 : 0.96, while molar ratio of Sn : S was 1 : 0.84. The surface morphology described the arrangement of the grains on the surface of the thin film with sizes ranging from 0.2 to 0.5 microns. Color similarity on the surface of the SEM images proved a homogenous thin layer.