SPIN JURNAL KIMIA & PENDIDIKAN KIMIA

SYNTHESIS AND CHARACTERIZATION OF CRAB SHELL CHITOSAN SOLID ELECTROLYTE POLYMER (SPE) MEMBRANE

Mu'ayanah — 2025-02-10

Efforts to prevent a global energy crisis by using renewable and environmentally friendly energy. Batteries are an alternative to replace non-renewable energy. However, in the battery, there is an electrolyte component which when finished using the battery will cause waste that causes the soil to become toxic. This study aims to determine the characterization of chitosan solid electrolyte membranes, in crab shells. The characterization carried out is the characterization of crab shell chitosan using an FTIR spectrophotometer, ion conductivity analysis of solid electrolyte membranes using an LCR Meter, and tensile tests using Tensilon. The method used in this research is experimental. Isolation of chitin and chitosan from crab shells was carried out in several stages, namely deproteination, demineralization, and deacetylation. The chitosan-lithium membrane was prepared by casting method with the addition of 15% lithium salt. The value of the degree of deacetylation in crab shell chitosan is around 39.39%. Based on the characterization, the chitosan-lithium SPE membrane conductivity value is 1.11 x 10-7 S.cm^-1 with a tensile strength value of 27.07 MPa.

ANTIBACTERIAL ACTIVITY TEST OF WATER APPLE LEAF EXTRACT Syzygium aqueum (Burm.f) Alston AGAINST Salmonella typhi BACTERIA USING ELISA READER

Salina Zulfiana — 2024-12-20

The water apple plant Syzygium aqueum (Burm. f) Alston is one of the plants used as traditional medicine due to its secondary metabolites such as flavonoids, steroids, terpenoids, alkaloids, tannins, phenols, saponins which can be utilized as antibacterials, antioxidants and others. This research aims to determine the IC₅₀ antibacterial activity of the water apple leaf extract against Salmonella typhi ATCC-14028 bacteria in inhibiting bacterial growth. Extraction was carried out using multi-step maceration using n-hexane, ethyl acetate, and methanol as solvents to obtain the concentrated extracts. Antibacterial activity test was conducted by using the microdilution method on Mueller Hinton Broth media by calculating optical density (OD) values at concentrations of 500 ppm, 250 ppm, 125 ppm, 62.50 ppm, 31.25 ppm, 15.63 ppm, 7.831 ppm, and 3.906 ppm. The optical density value was measured at a wavelength of 595 nm by Elisa microplate reader. Phytochemical contents were investigated and the presence of flavonoid, phenol, steroid, and terpenoid compounds in the extracts was indicated. Water apple leaf extracts have antibacterial activity in inhibiting the growth of Salmonella typhi ATCC-14028 bacteria showing an IC₅₀ value of n-hexane, ethyl acetate, and methanol extracts of 155,607 ± 30,592 µg/mL, 56.492 ± 50.124 µg/mL, 107.96 ± 50.124 µg/mL which is categorized as weak, strong, and moderate respectively.

INTEGRATION OF SOCIO-SCIENTIFIC ISSUES IN CHEMISTRY LEARNING OUTCOME TESTS TO MEASURE HIGH SCHOOL STUDENTS SCIENTIFIC EXPLANATION SKILLS

Annida Fadlila Hanan — 2024-12-20

Socio-scientific issues (SSI) are controversial issues related to socio-science. SSI can be integrated into chemistry learning outcome tests to measure students’ scientific explanation skills. This research aimed to develop a socio-scientific issues based test to measure the scientific explanation skills of high school students in acid-base material. The development model used is an exploratory mixed method. Qualitative data were collected through needs analysis, literature studies for references for initial test development, expert feasibility test, and usability feasibility test (qualitative) to obtain input from experts and reviewers. The results of the quantitative test showed that the test developed has an ideal percentage of 87% (Very Good) according to the reviewer and 71% (Good) according to the students. The number of valid items based on the item fit test was 15. A total of 10 questions have the discrimination category very good, 3 questions were good, 1 question was fair, and 1 question was not able to discriminate. The difficulty level test revealed that 26,67% of the questions were very difficult, 26,67% of the questions were difficult, 33,33% of the questions were easy, and 13,33% of the questions were very easy. The Cronbach Alpha reliability value of the test was 0.77, categorized as good.

THE EFFECT OF PROBLEM BASED LEARNING MODELS BASED ON SOCIO-SCIENTIFIC ISSUES ON STUDENTS' CRITICAL THINKING SKILLS ON HYDROCARBON BURNING MATERIALS

Dewi Linda Ardianti — 2024-12-20

Critical thinking skills in high school chemistry are still relatively low. One of the factors that causes students' low critical thinking skills is teachers who still dominate learning activities. This research aims to determine the effect of the Problem Based Learning (PBL) model based on Socio-scientific Issues (SSI) on students' critical thinking skills on hydrocarbon combustion material. This research was carried out at SMAN 11 South Tangerang City. The research method used in this research is a quantitative method with a quasi-experimental research method. The research sample was XI IPA 1A (as the experimental class) and XI IPA 1B (as the control class) with 16 students each. The instrument used was a description test with 22 questions representing 12 indicators of Robert H. Ennis' critical thinking. The results of the N-Gain data hypothesis test using the t-test (Independent Sample t Test) obtained a sig (2-tailed) < ?, namely 0.00 < 0.05 so H₁ was accepted and H₀ was rejected. This shows the influence of the problem based learning model based on socio-scientific issues on students' critical thinking skills on hydrocarbon combustion material.

DEVELOPMENT OF DIGITAL COMIC BASED LEARNING MEDIA (CHEMTOON) WITH MARVEL APP ON CORROSION MATERIALS

siti Hana Irawarni Alfu — 2024-12-20

This research project aims to design, develop and assess the feasibility of using chemical digital comic learning media (chemtoon) with the Marvel App on corrosion materials. Apart from that, to find out students' responses to digital comic learning media (chemtoon) with the Marvel App on corrosion material. Research uses methods research and development (R&D), with the ADDIE development model. The population of this research is all students in class XII Science. The sampling technique was purposive random sampling, obtained class XII-F Science, totaling 32 students as an experimental class. The results of media validation in developing digital comic-based media in the Marvel App show a V_count value from media expert validators is greater than V_table with a value of 0.85 – 0.95 > 0.80 , while the material expert assessment of all aspects shows a value of V_count greater than V_table with a value of 0.85 – 1 > 0.80. The results of student responses to digital comics obtained an average percentage of all aspects, namely 91.71%. This shows that the digital comic learning media (Chemtoon) with the Marvel App on corrosion material is valid, suitable for use and helps students' understanding of chemistry in corrosion material.

DEVELOPMENT OF PROBLEM BASED LEARNING TEACHING MODULES ON GREEN CHEMISTRY MATERIALS

Rahmah Khoirunnisa — 2024-12-20

The change from the 2013 curriculum to an Merdeka curriculum requires adjustments for teachers and students. The lack of availability of teaching tools that are in accordance with the Merdeka curriculum and a learning approach that is still teacher-centered makes students less motivated to participate in learning. The purpose of this study is to develop a PBL-based teaching module on green chemistry material by determining the validity, practicality, and effectiveness of student responses to the content measured in the teaching module. This research is R&D (Research and Development) research with the ADDIE (Analyze, Design, Develop, Implement, Evaluate) model. The data collection technique used a material and media validation questionnaire involving seven material and media expert validators and was analyzed using the Aiken's V test. Furthermore, the validated teaching module was tested limited to 26 class X phase E students. The development of this PBL-based teaching module obtained results in the validity of the material and media of 0.91 and 0.92 in the "Valid" category. Then it was implemented with students in class X-5 and received a response of 83.27% in the "Very Practical" category. Furthermore, the results of the LKPD assignment in the module obtained an average of 83.15% which indicates "Very Effective". Thus, this PBL-based teaching module is suitable for use as a learning tool.

DEVELOPMENT OF A SCIENCE (CHEMISTRY) PROJECT TEACHING MODULE IN THE MERDEKA CURRICULUM AS A TEACHER’S GUIDE FOR LEARNING IN CLASS X VOCATIONAL SCHOOLS

Felia Aura Diva — 2024-12-20

This research is a development research that aims to produce an IPAS (Chemistry) Project teaching module as a teacher's guide in learning, which is feasible in terms of validity and practicality. This module development adapts the 4D model (Define, Design, Develop, Disseminate) because the stages are arranged in detail and systematically, involving revisions, trials, and validation by experts. The test subjects were class X students of SMKN 1 Narmada with the Agribusiness of Agricultural Product Processing (APHP) expertise program. The research instruments included validation sheets and student and teacher response questionnaires. Data analysis used descriptive statistics, with module validity calculated using Aiken's V formula, and module practicality analyzed using a Likert scale. The results showed the average validity of the four validators was 0.861, which was classified as very valid. The level of understanding between validators was tested using the Percentage of Agreement (R) method, resulting in an average of 0.90 with a reliable category. The practicality of the module based on teacher and learner response questionnaires showed an average percentage of 94% and 81%, respectively. Based on these results, it can be concluded that the IPAS (Chemistry) Project teaching module on substance material and its changes for class X SMK has a high level of validity and practicality, so it is suitable for use in the learning process.

THE THE EFFECT OF HCl ACTIVATOR CONCENTRATION ON THE EFFECTIVENESS OF ACTIVATED CARBON DERIVED FROM CORNCOBS FOR METHYLENE BLUE ADSORPTION

Dyah Setyaningrum — 2024-12-20

This study aimed to investigate how activator hydrochloric acid (HCl) concentration affects the adsorption capacity of corncob-activated carbon in Methylene Blue (MB) dye. This was followed by immersion in HCl solutions with various concentrations (2.5 M; 3M; 3.5 M; and 4 M) as chemical activating agents. Next, FTIR and XRD were used to characterize the activated carbon that had been activated and unactivated. The study analyzed the reduction of methylene blue dye concentration in the air to evaluate the effectiveness of activated carbon as an adsorbent. It examined various factors influencing the adsorption process, including different initial concentrations of the azo dye (20 ppm, 30 ppm, 40 ppm, 50 ppm, and 60 ppm) and contact times (15, 30, 45, and 60 minutes). The experimental results indicated that a 3 M concentration of HCl was the most effective activator, leading to a maximum dye removal rate of 80.77%. For an initial concentration of 20 ppm of the azo dye, the highest adsorption results were achieved at 85.67%. Furthermore, the optimal contact time for maximum adsorption was found to be 30 minutes, with a peak adsorption rate of 70.08%. The Langmuir adsorption isotherm model demonstrated a better fit for the adsorption of methylene blue onto corncob-activated carbon. It can be concluded that activated carbon produced from corn cobs and treated with HCl is an effective adsorbent for reducing methylene blue levels in the solution.

COMPUTATIONAL STUDY: THE EFFECT OF BASIS SET ON THE ENERGY STABILITY OF HYDROCARBONS AND HALOGENIC ACIDS

Nilawati — 2024-12-20

This research is motivated by the many base sets contained in computational calculations. The selection and use of base sets play an important role in determining the accuracy of the calculation of theoretical molecular properties as well as in lowering the BSSE (base set superposition error). This study aims to analyze the influence of base set variations on the calculation of hydrocarbon and halogen acid energy stability using computational methods. The research method used is an experimental method. Molecular modeling using Avogadro software with the molecules used are halogen acid molecules and alkanes C1 - C5. The calculation uses NwChem software with the DFT method, functional BL3YP with 4 different base sets, namely STO-3G, 321-G, cc-pVDZ, and cc-pVTZ. The resulting data is then analyzed and compared with database calculations. The results of the study show that the higher the base set used, the more accurate the calculation results obtained. The base set that shows the most accurate results in this study is cc-pVTZ. However, it should be noted that the most accurate set bases can be different for each molecule.

SYNTHESIS AND CHARACTERIZATION OF SnO2/ZnO COMPOSITE USING JAPANESE PAPAYA LEAF EXTRACT (Cnidoscolus aconitifolius) WITH HYDROTHERMAL METHOD

Heni Puspita — 2024-12-20

SnO₂/ZnO composites were synthesized using the hydrothermal method using Japanese papaya (Cnidoscolus aconitifolius) leaf extract. This study aims to determine the effect of using Japanese papaya leaf extract (Cnidoscolus aconitifolius) on the formation of crystallinity and morphology in synthesizing SnO₂/ZnO composites. Synthesis was carried out with variations in mass of 5, 10, and 15 grams using the hydrothermal method for 12 hours at 160°C. The results of X-Ray Diffraction (XRD) characterization show that wide diffractogram peaks are identified as the peaks of the SnO₂ compound with a tetragonal structure and sharp peaks are identified as the peaks of the ZnO compound. The Fourier Transform Infrared (FTIR) characterization shows the peak wave number of 665 cm^-1 which is the Sn-O-Sn strain and the peaks at wave numbers 598 cm^-1 and 501 cm^-1 which are the Zn-O strain. Characterization of Scanning Electron Microscopy (SEM) in the synthesis of SnO₂/ZnO composites after adding Japanese papaya (Cnidoscolus aconitifolius) leaf extract had relatively reduced particle size and aggregate formation compared to no extract. The best effective mass of Japanese papaya leaf extract (Cnidoscolus aconitifolius) is the mass variation of 15 grams with 28.49 nm crystals.

DEVELOPMENT OF CHEMISTRY TEACHING MODULE BASED ON DIFFERENTIATION LEARNING TO IMPROVE STUDENT LEARNING OUTCOMES ON ATOMIC STRUCTURE MATERIAL

Ajeng Hartati — 2024-12-20

Atomic structure material is relatively complex and abstract material so it requires in-depth understanding and good visualization so that it is easy for students to understand. Differences in students' initial understanding and learning styles are the trigger for low student learning outcomes in atomic structure material. The solution is to apply differentiated learning. This research aims to develop a chemistry teaching module based on differentiated learning that can improve student learning outcomes in atomic structure material, especially in electron configuration material and the periodic system of elements. This development research uses the ADDIE model. The results of the research show that the chemistry teaching module based on differentiated learning in atomic structure material obtained a very feasible category in the material field with a percentage of 89.76% and obtained a very feasible category in the media field with a percentage of 88.59%. The chemistry teaching module based on differentiated learning is effective in improving student learning outcomes as shown by the acquisition of the Wilcoxon test, namely the Asymp.Sig value. (2-tailed) is 0.000. The results of students' responses to the chemistry teaching module based on differentiated learning on atomic structure material obtained an average percentage of 82.38% in the very good category, so that the chemistry teaching module based on differentiated learning on atomic structure material is suitable for use as a learning medium that can help participants. students to improve their learning outcomes.