This research purpose to determine the effectiveness of the liquid smoke of the Hevea braziliensis  fruit shell  against the activity of Escherichia coli bacteria. The preparation and purification of liquid smoke is carried out by 4 stages: pyrolysis , sedimentation, stage 1 and stage  2  distillation. This research was started with total acidity test, phenol level, pH and density with result of measurement 4,725% total acid content, 0,84% phenol content, 2,548 pH and 1,004 in density . An antibacterial test  using disc diffusion method by looking at the diameter of the clear zone. There are six concentrations of liquid smoke of  H.braziliensis  rubber shell used, negative control using aquades and positive control using ciprofloxacin . An  effective concentration was found in inhibiting E.coli is 100% concentration with a clear zone diameter of 11.3 mm. The result of analysis using One Way ANOVA showed F count (4.42)> F table (3,23), then H0 rejected, meaning there is a significant difference of influence of concentration to the diameter of clear zone produced.

The use of teaching material developed from laboratory research is one way that can be done to improve students' scientific literacy in accordance to the challenges of 21 st century learning. This research aimed to resolve the feasibility of the developed analytical chemistry module, to improve students' scientific literacy, and the student's response to the use of the module in the analytical chemistry course. The module was developed using the 4D type of Research and Development method, i.e., Define, Design, Develop, and Disseminate. The quality of module was determined by an expert validation test. The scientific literacy was measured by a pre-test and post-test with essay questions. Relied on the results of expert validation, the module results on the content eligibility aspect of 92%, the presentation feasibility aspect of 85%, the language assessment aspect of 88.3%, the graphic assessment aspect of 83.3%, and overall results of 87.5% with a very good category. The averages of pre-test and post-test scores were 28.67 and 82.74. Based on the results of the hypothesis test, it was concluded that there was an increase in students' scientific literacy by using a module in the analytical chemistry course. The students' response to the use of the module in learning activities was 82.00% with a very good category and the assessment of the module was 86.17% with a very good category.

Engine and machine oils, better known as lubricant, is a fast-moving part within the motorcycle and automobile industries. Due to its high demand, these oils are often counterfeited by irresponsible people to get more profit. The thing most often done to adulterate oil is by mixing it with other low-quality or used oil. Here, we propose a simple analytical method to identify oil adulteration by using UV-Visible spectroscopy. A number of 425 genuine and adulterated oils were used as samples. After appropriate dilution using n-hexane, the samples were analyzed by UV-Visible spectrophotometer followed by Principle Component Analysis (PCA) and Principle Component Regression (PCR) as part of the chemometrics analysis. The results show that prediction samples were accurately classified into their corresponding groups with PCA scores of 49% and 27% for principal component 1 and 2, respectively. PLS model achieved a good prediction to detect lubricant oil adulteration, with R-Square of predicted and reference samples were 0.9257 and 0.9204, respectively. The proposed method shows a promising alternative to the conventional chemical method using a more sophisticated instruments such as GC-MS and HPLC for oil or other organic compound identification.

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