This research aims to apply and find out the characteristics of Problem-Based Instrumental Analysis of Chemistry Lab Work Learning Model (IACLLM) which is able to build the characters, improve the conceptual mastery and the ability of problem solving. The research using experimental quasy with 2 student groups of pre service chemistry teachers as the subjects of the research applied the treatment of problem-based IACLLM for the experimental class and lab work learning with standard lab work procedure in control class. Conceptual mastery was measured using essay test; problem solving skills were measured using assessment of problem solving reports, presentation of the results, and kit making products; whereas the emerged characters were observed during the learning process. The result of this research showed that problem-based IACLLM had open-ended problem characteristic, had produced local material kit, and characters were observed in every stage of problem-based learning model. The implementation of the model could improve the spectrometric and electrometric conceptual mastery, the problem solving skills on a very good level and also some characters were developing during learning process, including religious, discipline, honest, curious, creative, critical, cooperative, communicative, independent, and able to appreciate other people's opinions and achievements, leadership, democracy, and able to be thorough and careful, and hardworking.

Abstract. Extraction and isolation of papaya seeds and leaves (Carica papaya L) has been performed using n-hexane and ethanol solvents. Further isolation of the extract obtained using ethyl acetate and diethyl ether solvents. The result of the phytochemical test of papaya extract obtained by mixture of an active compound of flavonoids, alkaloids, tannins, steroids, and saponins. Ethyl acetate isolates containing only flavonoids and diethyl ether isolates contain only alkaloids. Extracts and isolates from papaya plants had gram-positive antibacterial activity greater than the gram-negative bacteria, but both did not have antifungal activity. Papaya extracts have greater antibacterial activity than flavonoid isolates and alkaloid isolates. Strong antibacterial inhibitory sequences are extracts of papaya plants, flavonoid isolates, and alkaloid isolates.

The aim of this research is to develop nanomaterials for coating applications. This research studied the effect of various TiO2-SiO2 composites in acrylic paint to enhance the hydrophobic properties of the substrate. Titanium dioxide containing silica in the range 20–35 mol% has been synthesized using sol–gel route. The XRD’s spectra show that increasing SiO2 content in the composite, decreasing its crystalline properties but increasing the surface area. TiO2-SiO2 composite was dispersed in acrylic paint in 2% composition by weight. The largest contact angle was 70, which produced by the substrate coated with TS-35-modified acrylic paint. This study also investigated the enhanced photo-activity of TiO2-SiO2 modified with poly-aniline. The XRD spectra show that the treatment does not change the crystal structure of TiO2. The photo-activity of the composite was evaluated by degradation of Rhodamine-B with visible light. The best performance of the degradation process was handled by the composite treated with 0.1mL anilines per gram of TiO2-SiO2 composite (TSP-A). On the other side, the contact angle 70 has not shown an excellent hydrophobic activity. However, the AFM spectra showed that nanoroughness has started to form on the surface of acrylic paint modified with TiO2-SiO2 than acrylic alone.

This research aims to develop chemistry project-based learning with an Integrated Ethnoscience Approach in Science, Technology, Engineering, and Mathematics (Ethno-STEM) to improve students' conservative and entrepreneurial character. The research method refers to the Research and Development (R&D) model with the Four D by Thiagarajan (1997). The research samples are chemistry education students from Universitas Negeri Semarang. The model effectiveness test was conducted in secondary metabolite lectures at the Department of Chemistry, Faculty of Mathematics and Natural Science, Universitas Negeri Semarang, Indonesia. Data collection techniques used expert validation sheets to assess the feasibility of the model and observation sheets and questionnaires to measure students' conservative and entrepreneurial character. Based on the results of research, it was concluded that a chemical project-based learning model for the secondary metabolites course on essential oils and terpenes and learning tools with an Ethno-STEM approach was feasible and effective for improving students' conservative and entrepreneurial character with moderate and high criteria based on the N-gain score. The chemical batik motif on canvas based on the secondary metabolites' chemical structure is attractive and creative.

The ethnoscience approach is carried out by integrating local wisdom culture in science learning. The Minang community believes that the Taxus sumatrana plant is a cancer drug. But they have not been able to explain its benefits conceptually based on scientific inquiry with relevant references. This study aims to solve these problems through (1) designing ethnoscience-based inquiry learning to study the bioactivity of Taxus sumatrana; and (2) describe scientific experiments on plants as cancer drugs. This research includes qualitative research to reconstruct scientific explanations based on local wisdom. The data were obtained through observations at the research location regarding community local wisdom and laboratory activities including isolation, phytochemical identification, and chemical structure testing using Perkin Elmer 100 FT-IR spectroscopy. All data obtained were analyzed and corroborated by various relevant sources. The results of the analysis concluded that the appropriate learning design was an integrated model; and secondary metabolites found in the bark and leaves of Taxus sumatrana were tested using water, ethanol, ethanol + n-hexane, and ethanol + benzene as solvents, including terpenoids, alkaloids, terpenoids, steroids, phenolics, and saponins. The results showed that Taxus sumatrana can act as an anticancer because in the experimental laboratory it is known that terpenoids as taxols, phenolics, and other oxygenated metabolites which have the potential to be anticancer.