Hydrogen: Jurnal Kependidikan Kimia (Hydrogen: Journal of Chemistry Education, e-ISSN: 2656-3061 & p-ISSN: 2338-6487) is an open-access scientific periodical journal published by the Department of Chemistry Education, Faculty of Applied Science and Engineering, Mandalika University of Education. It contains research and review articles covering studies in chemistry education at schools, higher education, and communities and pure or applied studies in chemistry. Journal title : Hydrogen: Jurnal Kependidikan Kimia Initials : H-JKK Abbreviation : Hydrogen. Jurnal. Kependidikan. Kimia Frequency : Bimonthly DOI : 10.33394 ISSN : 2338-6487 (Print) | 2656-3061 (Online) Editor-in-chief : Yusran Khery (BNSP-Certified Editor) Publisher : Department of Chemistry Education, Faculty of Applied Science and Engineering, Mandalika University of Education Indexed : SINTA | Google Scholar|GARUDA Acreditation : Sinta 4 204/E/KPT/2022| Download Certificate All submitted manuscripts will be subjected to the peer-review process following a thorough inspection by the editors. The journal is published in both printed and online versions. The online version is free to access and download. Hydrogen: Jurnal Kependidikan Kimia (Hydrogen: Journal of Chemistry Education) was first published in 2013. During the period of 2013-2022, Hydrogen was published twice a year (June and December). Due to a large amount of interest from the author, Hydrogen publishes bimonthly in February, April, June, August, October, and December starting by 2023. Authors across the globe are welcome to submit their papers to the prestigious journal by fulfilling the requisite criterion. Every manuscript sent to the editorial office of the journal ought to follow the writing guidelines. If the manuscript does not meet the guidelines or is written in a different format, the article will BE REJECTED before further review. Only submitted manuscripts that meet the journal's format will be processed further. Hydrogen: Jurnal Kependidikan Kimia (Hydrogen: Journal of Chemistry Education) collaborated with: LPPM UNDIKMA This journal has been ACCREDITED by the National Journal Accreditation (ARJUNA) Managed by the Ministry of Education, Culture, Research, and Technology, Republic Indonesia with Fourth Grade (SINTA 4) starting from 2022 to 2026. Decree Number: 1429/E5.3/HM.01.01/2022 Hydrogen: Jurnal Kependidikan Kimia (Hydrogen: Journal of Chemistry Education) provides immediate OPEN ACCESS to its content on the principle that making research freely available to the public supports a greater global exchange of knowledge. All published articles will be assigned with DOI (Digital Object Identifiers). The DOI of the journal is https://doi.org/10.33394/hjkk.xxxxx.xxxxÂ
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Cognitive and Emotional Engagement in Stoichiometry Learning: A Correlational Study
The purpose of this study was to measure the strength of the relationship between students’ cognitive and emotional engagement in stoichiometry learning. This research employed a descriptive quantitative approach, including descriptive analysis and correlational analysis. The participants consisted of 70 eleventh-grade students enrolled in the science-track chemistry course, drawn from two classes: Grade XI Chemistry 1 and Grade XI Chemistry 2. Data were collected using a four-point Likert-scale questionnaire measuring cognitive and emotional engagement, as well as through observations, semi-structured interviews, and documentation. The results showed that: (1) students’ cognitive engagement was categorized as very high (13%), high (34%), low (43%), and very low (10%); (2) students’ emotional engagement was categorized as very high (20%), high (16%), low (53%), and very low (11%); (3) the correlation test between cognitive and emotional engagement was significant (0.000 < 0.05), indicating a positive relationship; and (4) the strength of the relationship between cognitive and emotional engagement, as indicated by Spearman’s rho, was 0.447, which represents a moderate level of correlation. Therefor, higher cognitive engagement is associated with higher emotional engagement, and vice versa.
Copyright (c) 2026 Waviza, Erlina, Eni Mayasari https://creativecommons.org/licenses/by/4.0
Project-Based Learning in Basic Chemistry Practice: Its Impact on Vocational Students’ Analytical Abilities
Vocational chemistry education is expected to develop not only procedural competence but also higher-order analytical abilities aligned with industrial demands. However, Basic Chemistry Practice in vocational high schools is often dominated by teacher-centered instruction, limiting students’ capacity to interpret experimental data and connect theory with practice. This study aimed to examine the impact of Project-Based Learning (PjBL) on vocational students’ analytical abilities and to explore students’ and teachers’ perceptions of its implementation. A quantitative pre-experimental design using a one-group pretest–posttest model was employed. The participants were 34 Grade X Industrial Chemical Engineering students at a vocational high school. Analytical ability was measured using HOTS-based open-ended questions aligned with Bloom’s revised taxonomy, and perception data were collected through Likert-scale questionnaires. Statistical analysis included the Shapiro–Wilk normality test, paired sample t-test, and normalized gain (N-gain) analysis. The results showed a significant improvement in analytical ability, with the mean score increasing from 41.0 to 73.5 (p < 0.001) and an N-gain value of 0.55, categorized as moderate. Students and teachers reported highly positive perceptions, particularly regarding engagement, collaboration, and analytical skill development. These findings suggest that PjBL provides an effective pedagogical framework for strengthening analytical competence in vocational chemistry practice. The novelty of this study lies in the integration of HOTS-based assessment into authentic vocational chemistry projects within a PjBL framework, an approach that is still rarely reported in vocational chemistry education. By combining learner-centered project implementation with structured higher-order thinking assessment, this study offers a practical and context-relevant model for improving analytical competence in vocational education settings.
Copyright (c) 2026 Amro Hafiz Munawan, Citra Ayu Dewi, Suryati https://creativecommons.org/licenses/by/4.0
CHEMLIT: Development and Feasibility of a Sensor-Based Chemistry Practicum Tool for Electrolyte Solutions
Chemistry learning requires the integration of macroscopic, submicroscopic, and symbolic representations. However, limited availability of practicum tools in senior high schools often hinders students’ comprehensive understanding of chemical concepts, particularly in electrolyte and nonelectrolyte solutions. This study aimed to develop and implement CHEMLIT, a sensor-based chemistry practicum tool designed to support learning on solution electrical conductivity. The study employed a Research and Development (R&D) approach using the ADDIE model, consisting of analysis, design, development, implementation, and evaluation stages. Needs analysis was conducted through classroom observations and teacher interviews, followed by prototype design, assembly, calibration, and functional testing to ensure stability and safety. The implementation involved two senior high schools in the Minahasa region, with chemistry teachers serving as reviewers and students as trial users. Feasibility was evaluated by media experts, material experts, teachers, and students using five-point Likert-scale questionnaires, and the data were analyzed by converting scores into percentage-based feasibility criteria. Product feasibility was evaluated through validation by media experts, subject matter experts, chemistry teachers, and students using questionnaire instruments. The validation results indicated a very high level of feasibility, with scores of 91.7% from media experts, 96% from material experts, 92% from teachers, and student responses exceeding 93.99%, categorized as very good. These findings indicate that CHEMLIT meets technical, visual, and content feasibility standards and can serve as an alternative practicum tool for teaching electrolyte and non-electrolyte solutions, especially in schools with limited laboratory facilities. Its novelty lies in a portable sensor-based design that integrates quantitative conductivity measurement into conventional testing without complex digital systems.
Copyright (c) 2026 Lorry Enjlina Br Surbakti, Maria Murniyanti Parhusip, Natasya Patulak, Septiany Ch. Palilingan, Stefan Marco Rumengan, Jakub Saddam Akbar https://creativecommons.org/licenses/by/4.0
Development of A Virtual Laboratory for Electrochem to Support Students' Critical Thinking Skills
The application of interactive learning media plays an important role in stimulating motivation and deepening students' understanding, especially in bridging the characteristics of abstract chemistry learning, one of which is the material of electrolyte and non-electrolyte solutions. The main problem in chemistry learning in Madrasah Aliyah is the limited physical laboratory facilities, which impacts the low critical thinking skills of students. This study aims to develop a Virtual Laboratory "Electrochem Lab" that supports critical thinking skills and to test its feasibility conceptually and practically. As a supporting instrument, Electrochem Lab is equipped with an evaluation feature in the form of a quiz consisting of 5 questions based on Higher Order Thinking Skills (HOTS) that have been adjusted to train students' critical thinking skills independently. The study adopts a Research and Development (R&D) framework, specifically following the Lee & Owens model, which progresses through phases of analysis, design, development, implementation, and evaluation. The experimental subjects involved two experts (materials and media), one chemistry teacher, and 13 students of grade XI IPA MAN 5 Batang Hari consisting of 3 students in one-to-one tests with heterogeneous cognitive representations and 10 students in small group tests. The data collection instrument used a Likert Scale questionnaire consisting of a media expert questionnaire and a material expert questionnaire, a student response questionnaire and a one-to-one trial instrument. Evidence of the validity of the instrument and product was obtained through expert assessments stating that the media was very suitable for testing. The results showed a feasibility percentage of 90% from media experts and 89.23% from material experts, both of which were considered very suitable. The practitioner's assessment (chemistry teacher) reached 94.55%, while the one-to-one test reached 86,6% and the small group trials reached 98% with a very good category. It can be concluded that the Android-based virtual laboratory "Electrochem Lab" is very suitable to be used as an innovative solution to bridge the understanding of abstract concepts through sub-microscopic visualization and support the training of students' critical thinking skills. The novelty of this research lies in the integration of a contextual approach in digital simulations that connect learning materials with the students' surroundings and the Madrasah Aliyah environment.
Copyright (c) 2026 M Rizki, Rayandra Asyhar, Isra Miharti, Zurweni, Firdiawan Ekaputra https://creativecommons.org/licenses/by/4.0
The Effect of Spiritually Integrated Chemistry Learning on Learning Outcomes Moderated by Spiritual Quotient (SQ) Levels
Indonesian students' science performance remains low based on PISA 2022 results, particularly in abstract chemistry concepts such as acid-base. This study aims to analyze the effect of chemistry learning integrated with spiritual values on students' learning outcomes moderated by Spiritual Quotient (SQ) levels. A quasi-experimental method with a 2 × 2 factorial design was employed, involving 60 eleventh-grade students selected through purposive sampling. The experimental class (n = 30) applied Problem Based Learning (PBL) integrated with seven spiritual values (awareness, elegance, meaningfulness, transcendence, truth, peace, wisdom) through motivation, reflection, and contemplation, while the control class (n = 30) used PBL without spiritual values integration. Data were collected using a 20-item multiple-choice test (KR-20 = 0.95) and a 19-item SQ questionnaire adapted from Indaty N. (2022) based on Zohar and Marshall's (2000) theory (Cronbach's alpha = 0.872). Two-Way ANOVA results revealed that spiritually integrated chemistry learning significantly improved learning outcomes (F = 25.697, p = 0.000). SQ level also significantly influenced learning outcomes (F = 46.060, p = 0.001). However, no significant interaction was found between learning model and SQ level (p = 0.224), indicating that both variables independently affect learning outcomes. Low SQ students in the experimental class (M = 81.79) achieved scores comparable to high SQ students in the control class (M = 85.00), suggesting that spiritual values integration can compensate for lower SQ levels. State of novelty in this study concludes that integrating spiritual values into chemistry learning enhances academic achievement and supports holistic education by connecting scientific concepts with students' life values.
Copyright (c) 2026 Andini Zahra, Ayi Darmana, Denada Septiani Yesa https://creativecommons.org/licenses/by/4.0
Development of a STEM-Based Activity Sheet to Train Critical Thinking in Reaction Rates
This study aims to develop a feasible STEM-based Student Activity Sheet on reaction rate material to train students’ critical thinking skills, based on aspects of validity, practicality, and effectiveness. The research employed a Research and Development (R&D) method using 4D model, which encompasses four sequential phases: define, design, develop, and disseminate. However, the implementation of this study is confined to the develop stage. The product was validated by two chemistry education experts and one chemistry teacher to assess content and construct validity. The practicality was evaluated through student response questionnaires and observation sheets, while its effectiveness was measured using pretest and posttest scores of critical thinking skills and learning outcomes analyzed through the N-Gain formula. The validation results showed a mode score of 4, which in valid category. The practicality test yielded a score of 92% from student responses and 97% from observation results, categorized as very practical. The effectiveness analysis demonstrated that most students achieved high N-Gain scores (g ≥ 0.7) in critical thinking indicators, with a significant improvement in learning outcomes from an average pretest score of 63 to a posttest score of 85. These findings indicate that the developed STEM-based LAPD is valid, practical, and effective to train students’ critical thinking skills on reaction rate material.
Copyright (c) 2026 Ardianti Dwi Agustin, Bertha Yonata https://creativecommons.org/licenses/by/4.0
Correlation between Metacognitive Awareness and Students’ Self-Efficacy in Chemistry Learning among Grade XII Students
This study aims to identify the relationship between metacognitive awareness and students’ self-efficacy in chemistry learning among grade XII students at MAN Pontianak. This research employed a quantitative approach with a descriptive correlational design involving 36 students selected through purposive sampling. The instruments used were the Metacognitive Awareness Inventory (MAI) questionnaire and a self-efficacy questionnaire, both of which had been validated and tested for reliability. Data were analyzed using descriptive statistics and the Pearson Product-Moment correlation test. The results showed that students’ metacognitive awareness was predominantly in the very well-developed category (66.7%), while self-efficacy was classified as very high (91.7%). The correlation analysis revealed a positive but weak and statistically insignificant relationship between metacognitive awareness and self-efficacy (r = 0.249; p = 0.144 > 0.05). These findings indicate that although both variables are at high levels, metacognitive awareness does not necessarily predict students’ self-efficacy in chemistry learning. This study contributes to the understanding of the complex interaction between cognitive and affective factors in chemistry education. Practically, the results suggest that teachers should not only develop students’ metacognitive skills but also implement instructional strategies that explicitly strengthen self-efficacy, such as providing mastery experiences, constructive feedback, and problem-based learning environments.
Copyright (c) 2026 Mutiara Tsani, Erlina, Eni Mayasari https://creativecommons.org/licenses/by/4.0
Development and Effectiveness of a Canva-Based Problem-Based Learning E-Module Using the 4D Model to Improve Students’ Understanding of Molecular Shapes
This study aims to develop and evaluate the effectiveness of a Canva-based e-module using the Problem-Based Learning (PBL) approach to improve students’ understanding of molecular shapes. The research employed a Research and Development (R&D) method using the 4D model (define, design, develop, disseminate). The effectiveness test applied a one-group pretest–posttest design involving 35 tenth-grade students at SMA Negeri 2 Medan selected through purposive sampling. The research instrument consisted of a multiple-choice test that was validated and tested for reliability (KR-20 = 0.811). Data analysis techniques included normality test, paired sample t-test, and N-gain analysis. The validation results showed that the e-module was highly feasible, with scores of 90.56% from media experts and 89.38% from material experts. The paired t-test results indicated a significant difference between pretest and posttest scores (p < 0.05), supported by an N-gain value of 0.76 (high category). These findings indicate that the Canva-based PBL e-module is both feasible and statistically effective in improving students’ understanding of molecular shapes.
Copyright (c) 2026 Ester Ndruru, Nora Susanti, Jhonatan Ariski Lumbantobing https://creativecommons.org/licenses/by/4.0
Theoretical Study of The Structure of Anthocyanin Dyes to Improve The Performance of Dye Sensitized Solar Cells (DSSCs)
In this study, anthocyanin dyes have been designed in two ways: without modification and with modification, incorporating donor chains and π-chains, and forming the structure of type D-π-A dyes. The anthocyanin dyes used are delphinidine, cyanidin, pelargonidin, malvidin, petunidine, and fragarine. Meanwhile, the modified molecule is a combination of anthocyanin dye as an acceptor chain, coumarin as a donor chain, and 1,4-dihydro-pyrrolo[3,2-b]pyrrole as a π-conjugation chain. The molecular structure was calculated using a 16W Gaussian Software with the DFT method and the B3LYP/6-31G base set. The results of the calculation on the dye without modification showed that the malvidin dye produced the smallest bandgap of 2.4085 eV and the largest light absorption. Meanwhile, the results of the calculation of the modified dye showed that the modified dye with the delphinidin acceptor produced the smallest bandgap of 1.4485 eV and the largest light absorption. In conclusion, modified anthocyanin dyes can improve the light absorption efficiency in DSSCs.
Copyright (c) 2026 Imelda, Jusmarni, Hermansyah Aziz, Elvira Deswita https://creativecommons.org/licenses/by/4.0
The Effect of Implementing the Practicum Method on Students' Learning Motivation in Reaction Rate Material
This study aims to determine the effect of the application of the practicum method on student learning motivation in the reaction rate material of class XI of SMA Negeri 11 Pontianak. This study uses a quantitative approach with a quasi-experimental design with a one group pretest–posttest design model. The research sample consisted of 36 students of class XI Chemistry 2 who were selected using the purposive sampling technique. Data collection was carried out using a learning motivation questionnaire consisting of 25 statements on a Likert scale. Data analysis included normality test, homogeneity test, Wilcoxon test, and N-Gain calculation. The results showed that the average student learning motivation increased from 61.02% (high category) before treatment to 87.36% (very high category) after the application of the practicum method. The increase occurred in all indicators of learning motivation with an increase of 23.77% to 30.19%. The results of statistical tests also showed a significant difference between learning motivation before and after treatment. These findings show that practicum activities not only increase students' motivation to learn, but also help students understand the concept of reaction rate more concretely through hands-on experience. The implication of this study is that the practicum method can be an effective learning strategy to increase student engagement, strengthen the understanding of abstract chemistry concepts, and create more active and meaningful learning in the classroom.
Copyright (c) 2026 Seto Hariono, Eny Enawaty, Rachmat Sahputra https://creativecommons.org/licenses/by/4.0
Development of Genially Based Learning Media based on Computational Chemistry on The Subject of Chemical Bonding of 11th Grade High School
This study aims to develop and assess the feasibility level of Genially-based interactive learning media that integrates computational chemistry into chemical bonding materials. The media is designed to be able to display a more concrete visualization of molecular structures, so that it can help students understand abstract concepts. This research is included in the type of Research and Development (R&D) with reference to the ADDIE development model. The instruments used include media validation sheets and material validation sheets that are prepared based on the standards of the National Education Standards Agency (BSNP) and assessed by experts, as well as questionnaires to find out student responses. The results of the needs analysis at SMA Negeri 13 Medan show that the use of technology by teachers in learning is still not optimal, so students tend to feel less interested and have difficulty understanding the material. Based on these conditions, Genially learning media based on computational chemistry on chemical bonding materials was developed as a solution to support students' learning needs. The validation results showed that the developed media obtained an average feasibility percentage of 92% from media experts and 89% from material experts. Meanwhile, student response to this media reached an average of 87%. The final product of this research is in the form of interactive digital learning media. Thus, it can be concluded that Genially's learning media based on computational chemistry on chemical bonding materials is included in the category of being very feasible to be used in the learning process.
Copyright (c) 2026 Devi Patricia Hutagalung, Dinda Suci Ramadhani, Asep Wahyu Nugraha https://creativecommons.org/licenses/by/4.0
Quality Analysis of Fermented Virgin Coconut Oil (VCO) Purified by Silica Slag Nickel Filtration
This study has been conducted on Quality Analysis of Fermented Virgin Coconut Oil (VCO) with Purification using Nickel Silica Slag by Filtration. This study aims to describe the physical, organoleptic and chemical qualities of fermented VCO purified with nickel silica slag. The results showed that the VCO result value obtained was 9.33% (v/v), with the organoleptic test of Fermentation VCO before and after filtration, namely colors 3.93 and 4; smells 3.20 and 3.27, and tastes 2.80 and 2.80. Determination of the physical quality of Fermented VCO with clarity values before and after respectively, Transmission 90.0% and 92.0%. Determination of the chemical quality of Fermented VCO before and after Filtration, namely the moisture content value of 0.31% and 0.08%, respectively; the value of free fatty acid content is 0.17% and 0.15%; The peroxide values were 0.53 mg eq/kg and 0.52 mg eq/kg, and the saponification values were 189.16 mg KOH/g and 249.30 mg KOH/g. The results of the chemical quality analysis in this study are in accordance with SNI No. 7381 of 2008 and SNI No. 7431 of 2015. Therefore, it can be concluded that VCO absorbed using nickel silica slag can improve its physical and chemical qualities.
Copyright (c) 2026 Nadyra Budiman, La Harimu, Rahmanpiu https://creativecommons.org/licenses/by/4.0
Photocatalytic Degradation of Crystal Violet Using CuFe₂O₄ in a Heterogeneous Photo-Fenton System with Ascorbic Acid
Crystal violet is a persistent dye that is difficult to remove using conventional treatment methods. This study investigates the degradation of crystal violet using a CuFe₂O₄-based heterogeneous photo-Fenton system in the presence of ascorbic acid. The novelty of this work lies in the combined use of CuFe₂O₄ and ascorbic acid to enhance redox cycling and improve degradation performance under photo-Fenton conditions. The CuFe₂O₄ catalyst was synthesized via a sol–gel method and characterized using Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD), confirming the formation of a spinel structure with an average crystallite size of 38.4 nm. The degradation process was evaluated by varying pH (1–9) and hydrogen peroxide (H₂O₂) concentration (10–50 mmol/L). The optimum pH was found to be 3, achieving a degradation efficiency of 94.38%, while the optimum H₂O₂ concentration was 30 mmol/L with a degradation efficiency of 93.56%.The improved degradation performance is attributed to enhanced hydroxyl radical (•OH) generation facilitated by the interaction between CuFe₂O₄ and ascorbic acid. These results suggest that CuFe₂O₄ with ascorbic acid can improve crystal violet degradation under the tested photo-Fenton conditions.
Copyright (c) 2026 Apri Rahmanisa, Indang Dewata, Mawardi, Romy Dwipa Yamesa Away https://creativecommons.org/licenses/by/4.0
Effect of Genially-Based Computational Chemistry Media on Students’ Motivation and Learning Outcomes in Chemical Bonding
This study was motivated by the low level of students’ motivation and learning outcomes in chemical bonding material at SMA Negeri 13 Medan, as indicated by low participation, limited conceptual understanding, and many students not achieving the minimum learning criteria. This study aimed to examine the effect of Genially-based computational chemistry media on students’ learning outcomes and to describe students’ learning motivation after its implementation. This research employed a quasi-experimental method with a pretest–posttest control group design. The sample consisted of 70 students, divided into an experimental class (n = 35) and a control class (n = 35). The experimental class was taught using Genially-based computational chemistry media integrated with discovery learning, while the control class used discovery learning without the media. The data were analyzed using N-gain and an independent sample t-test. The results showed that the experimental class achieved a higher increase in learning outcomes (N-gain = 0.72, high category) compared to the control class (N-gain = 0.63, medium category). The hypothesis test indicated a statistically significant difference between the two groups (t (68) = 3.74, p < 0.05). In addition, students’ learning motivation in the experimental class was categorized as high (81%). In conclusion, Genially-based computational chemistry media has a significant effect on improving students’ learning outcomes and positively contributes to students’ learning motivation. Therefore, this media can be used as an innovative alternative in chemistry learning, particularly for abstract topics such as chemical bonding.
Copyright (c) 2026 Dinda Suci Ramadhani, Devi Patricia Hutagalung, Asep Wahyu Nugraha https://creativecommons.org/licenses/by/4.0
Degradation of Methylene Blue by a Photo-Fenton System Based on Copper Ferrite Catalyst and Ascorbic Acid
Water pollution caused by methylene blue is difficult to treat due to its stability and resistance to conventional methods. This study aims to evaluate the performance of a CuFe₂O₄-based photo-fenton system enhanced with ascorbic acid. The catalyst was synthesized using the sol–gel method and characterized by FTIR and XRD. Degradation experiments were carried out under UV irradiation (5 W) by varying pH (1–9) and H₂O₂ concentration (1.5–15 mmol/L). Methylene blue concentration was measured using a UV–Vis spectrophotometer at a wavelength of 664 nm. The results show that degradation efficiency reached 98.48% at pH 3 and 10 mmol/L H₂O₂. This condition promotes efficient Fe²⁺ activation of H₂O₂ to generate hydroxyl radicals (•OH), while ascorbic acid accelerates the reduction of Fe³⁺ to Fe²⁺, sustaining the redox cycle and increasing radical availability. These findings demonstrate that the system is effective and has strong potential for wastewater treatment.
Copyright (c) 2026 Adika Nuzula, Indang Dewata, Desy Kurniawati, Jon Effendi https://creativecommons.org/licenses/by/4.0
Quality Analysis of Virgin Coconut Oil Resulting From a Combination of Fermentation and Controlled Heating Using Silica by Rice Husk Ash
Virgin Coconut Oil (VCO) has unique characteristics such as a very clear color resembling mineral water, low water and free fatty acid content, and high lauric acid content. The purpose of this study was to compare the quality of physical, chemical, and organoleptic parameters of VCO before and after adsorption with rice husk ash silica. The method used was adsorption. The adsorbent is arranged to a height of 4 cm with a flow rate of 14 drops per minutes. The results showed that the clarity test before and after adsorption was 85.8% and 97.9%. The water content before and after adsorption was 0.29% and 0.07%; free fatty acids were 0.49% and 0.17%; peroxide value was 1.98 mg eq/kg and 1.48 mg eq/kg; and saponification value was 189.34 mg KOH/g and 229.24 mg KOH/g. The average organoleptic color test before and after adsorption was 3.07 and 4; ordor was 3.33 and 3.2; and tastes 2.8 and 2.4, meet SNI 7381:2008 and SNI 2015. Thus, it can be concluded that rice husk ash silica can improve the quality of VCO.
Copyright (c) 2026 Fahdila Rahmadani, La Harimu, Rahmanpiu https://creativecommons.org/licenses/by/4.0
In Vitro Evaluation of the Anti-Diabetic Potential of Oxovanadium(IV) Complex with Terpyridine Ligand
An oxovanadium(IV) complex with 2,2′:6′,2″-terpyridine ligand, [VO(terpy)]SO₄, was synthesized and characterized to evaluate its anti-diabetic potential. The complex was synthesized via a direct reaction between VOSO₄ as the metal source and terpyridine ligand in solution and confirmed through conductometric and mass spectrometric analyses. Conductivity measurements indicated that the complex behaves as a 2:2 electrolyte in aqueous solution, dissociating into [VO(terpy)]²⁺ and SO₄²⁻ ions. Mass spectrometry revealed a peak at m/z 150.0098 corresponding to the cationic species. The anti-diabetic activity was evaluated through in vivo studies using alloxan-induced diabetic rats, demonstrating a significant reduction in fasting blood glucose levels. These findings suggest that the oxovanadium(IV)–terpyridine complex is a candidate for further development as an anti-diabetic agent.
Copyright (c) 2026 Fakhrotun Nisa, Djulia Onggo https://creativecommons.org/licenses/by/4.0
Antibacterial Activity Test of Staphylococcus aureus from Henna Leaf Extract (Lawsonia inermis Linn)
An antibacterial activity test against Staphylococcus aureus using henna leaf extract (Lawsonia inermis Linn.) has been conducted. This study aimed to determine the secondary metabolite components and the major compounds present in the henna leaf extract, as well as its inhibitory activity against Staphylococcus aureus. The secondary metabolite components were identified through phytochemical screening, while the major compounds were determined using GC-MS. The antibacterial activity was tested at concentration variations of 75%, 50%, 25%, and 12.5%. The resulting inhibition zones were then categorized according to standard criteria. The significance of the effect of concentration on the inhibition zones was analyzed using a one-way ANOVA test, followed by LSD test at α = 0.05. The results showed that the henna leaf extract tested positive for flavonoids, alkaloids, tannins, and quinones and GC-MS analysis shows compounds included 1,5-heptadiene-3,4-diol, 2-methyl-; 2-undecene, 2-methyl-; cyclotrisiloxane, hexamethyl-; 2,6-dihydroxyacetophenone; and 2,3-dihydroxybenzoic acid. The antibacterial activity test results showed that different concentrations (12.5%, 25%, 50%, and 75%) produced different inhibition zones; however, all were still classified within the same category, namely moderate. Statistical analysis indicates a significant effect of concentration on the inhibitory activity against the test bacteria, where F test = 4.771 > F crit = 4.066 at α = 0.05. Further analysis using the LSD test revealed two groups with significantly different inhibitory effects: the 75% and 50% concentration groups showed significantly higher inhibitory activity compared to the 25% and 12.5% groups.
Copyright (c) 2026 Laily Nurliana, Halimatussaddiyah Ritonga, Fatmawati, Rustam Musta https://creativecommons.org/licenses/by/4.0
Determination of Thorium Distribution Coefficient in Clay Soil From Bangka Belitung for Radioactive Waste Management
Radioactive waste is material contaminated by radioactive substances from nuclear activities that pose a danger to the environment and health, so controlled management is required. The purpose of this study was to test the distribution coefficient value of Bangka Belitung clay as an adsorbent to absorb thorium ions. Clay is used because of its large surface area, which helps the adsorption process of metal ions. The results of the study showed that the optimum adsorption conditions were achieved within 10 minutes with an optimum concentration of 100 ppm. Meanwhile, the results of the Langmuir isotherm analysis had a larger R2 value, namely 0.94923. This indicates that the adsorption process is more suitable for the formation of a monolayer. Based on these results, clay can be used in landfill systems to reduce the risk of groundwater pollution.
Copyright (c) 2026 Arya Diva Yana, Alizar, Dadong Iskandar, Hary Sanjaya, Jon Efendi https://creativecommons.org/licenses/by/4.0
Voltammetric Detection of Zn2+ Ions Using a Glassy Carbon Electrode Modified with Napa-Soil-Derived NiAl₂O₄
This study reports the development of a glassy carbon electrode (GCE) modified with NiAl2O4 derived from napa soil for the voltammetric detection of Zn2+ ions. The modified electrode was prepared using a drop-casting method and characterized in 4.0 mM K3[Fe(CN)6] with 0.1 M KCl as the supporting electrolyte. The results showed an increase in oxidation peak current from 19.93 µA (bare GCE) to 26.80 µA and reduction peak current from −19.03 µA to −24.29 µA after modification, indicating enhanced electron transfer. Zn2+ detection was carried out in the concentration range of 1–3 mM, where the reduction peak current increased from −85.49 µA to −170.83 µA with increasing concentration. A linear relationship between concentration and current response was obtained with a regression equation of y = -42.67x – 40.42 and a correlation coefficient (R2 = 0.9907), indicating good linearity of the sensor. The limit of detection (LOD) was calculated to be 0.21 mM. Among the tested supporting electrolytes, 0.1 M KCl provided the highest and most stable current response. Although the modified electrode shows improved performance, the detection range is still limited to the millimolar level, and further studies are required to evaluate selectivity, reproducibility, and applicability in real samples. These findings demonstrate the potential of napa-soil-derived NiAl2O4 as a sustainable and cost-effective material for electrochemical sensing applications.
Copyright (c) 2026 Dhea Septiani, Mawardi, Umar Kalmar Nizar, Okta Suryani https://creativecommons.org/licenses/by/4.0
Effect of Operating Temperature on Marine Fuel Oil (MFO) Quality Parameters
Marine Fuel Oil (MFO) is a residual fuel widely used in heavy industries, whose quality is influenced by refining operating conditions. This study aims to evaluate variations in key quality parameters of MFO, namely flash point, density, and viscosity, using samples obtained from a petroleum refinery in Riau, Indonesia. Data were collected through direct observation and laboratory testing during a 10-day industrial internship period using standardized ASTM methods. The results indicated that the flash point ranged from 61.83 to 73.50 °C, density ranged from 922.7 to 928.8 kg/m³, and viscosity ranged from 132.7 to 185.0 cSt. Variations in these parameters were observed during the monitoring period. However, further statistical analysis is required to confirm the strength and significance of the relationship between operating temperature and product quality. These findings highlight the importance of consistent monitoring and control of operating conditions to maintain product quality within industrial specifications.
Copyright (c) 2026 Nissa Atviona, Alizar Ulianas, Ihut Parulian https://creativecommons.org/licenses/by/4.0
The Impact of the Discovery Learning Model on Learning Outcomes in Basic Chemistry at SMAN 1 Sungayang
This study explores the effect of the Discovery Learning model on student learning outcomes in basic chemistry at SMAN 1 Sungayang. This is a quantitative study with a quasi-experimental design in the form of a nonequivalent control group. The study population consisted of all 10th-grade students, with a sample of two classes selected through purposive sampling. The experimental group used the Discovery Learning model, while the control group received conventional instruction. Data analysis included tests of normality and homogeneity, followed by hypothesis testing. The results indicate that the Discovery Learning model significantly improves student learning outcomes, demonstrating its effectiveness in promoting active engagement and a deeper understanding of chemical concepts. Thus, this model can be used as an alternative in chemistry instruction to improve the quality of student learning outcomes.
Copyright (c) 2026 Widia Rahmanda, Elvy Rahmi Mawarnis, Dwivelia Aftika Sari https://creativecommons.org/licenses/by/4.0
Promoting Multiple Representation in the TPACK Framework to Clarify the Acid-Base Species Problem-Solving
Oversimplifying chemical concepts to explain the invisible part is frequent in the concept of acid-base species determination. During school time, teachers frequently drill students to use straightforward formulas to prevent time-consuming calculations in calculating pH values. This attitude contributes to misleading problem-solving even among twenty-three preservice teachers at one of the educational universities in West Java, Indonesia. Therefore, the lecturer developed a learning strategy that uses the TPACK framework and multiple representations to clarify the misleading and prepare chemistry preservice teachers to overcome similar challenges in real-world situations. The multiple representations and misconceptions analysis was assigned to determine a suitable pedagogical strategy and identify appropriate technology. Quantitative assessments were used to measure changes in problem-solving approaches. It discovers that they have an excellent understanding of solving the acid-base problems using the conceptual approach, with increasing: 13.0% to 60.9% and 43.4% to 56.5%. However, some mathematical issues appear if the conditions are related to more complex acid-base scenarios, such as those related to buffer and hydrolysis regions. It is shown that the percentage of the conceptual approach usage decreases or remains constant: 69.6% to 45.7% and 43.4%, respectively. This shows that the symbolic level in chemistry learning is also linked to mathematical skills. As a consequence, chemistry preservice teachers must have a strong mathematical basic skills to solve problems correctly. Further study is also recommended in other chemistry subjects to get a broader view.
Copyright (c) 2026 Qonita Mu'minah, Sri Mulyani https://creativecommons.org/licenses/by/4.0
Development, Validation, and Practicality of a Wordwall-Based Educational Game for Senior High School Acid-Base Learning
This study aimed to develop and evaluate the validity and practicality of a Wordwall-based educational game for senior high school acid-base learning. The study employed a Research and Development (R&D) design using the ADDIE model, consisting of analysis, design, development, implementation, and evaluation stages. The developed media integrated game-based quizzes, instant feedback, visual elements, and concept-based challenges to support joyful learning and deepen students’ conceptual understanding of acid-base material. Data were collected through expert validation sheets, student response questionnaires, and a teacher interview. The product was validated by three expert validators and evaluated by one chemistry teacher. The implementation stage involved 29 students from class XI.F.1 and 31 students from class XI.F.2 at SMAN 10 Sijunjung. The validation results showed that the material aspect obtained a validity score of 80%, the language aspect obtained 75%, and the media design aspect obtained 95%, categorized as valid to highly valid. Student responses indicated that the media was very practical, with practicality scores of 86,75% in class XI.F.1 and 88,00% in class XI.F.2 in terms of ease of use, attractiveness, usefulness, and time efficiency. Teacher feedback also indicated that the media helped present acid-base concepts in a more interactive and engaging way. The findings indicate that the Wordwall-based educational game is feasible and practical for use as an alternative digital learning medium in acid-base instruction. Further research is recommended to examine its effectiveness on students’ conceptual understanding, learning motivation, and learning outcomes.
Copyright (c) 2026 Bunga Artika Sari, Elvy Rahmi Mawarnis, Dwivelia Aftika Sari https://creativecommons.org/licenses/by/4.0
Development Local Culture-Based Science E-Supplements with “Gerakan Kebiasaan Anak Indonesia Hebat” on Additives Substance
Science learning on additive materials in schools has not yet utilized local culture as a learning context, resulting in a gap between students’ real-life experiences and the scientific concepts studied in the classroom. “Gerakan 7 Kebiasaan Anak Indonesia Hebat” carried out by the Ministry of Primary and Secondary Education which is designed as a strategy in building positive habits in learning, especially the habits of liking to teach, eating healthy and nutritious, and socializing. This study aims to develop a science e-supplement based on the local culture of Kapuas Hulu Regency and to examine its feasibility and user responses. The development model used is ADDIE, limited to the Development stage. The research procedures include needs analysis through teacher interviews, design and development of the e-supplement, and validation by material, media, and language experts. Teacher and student responses were collected using questionnaires. The validation results indicate that the e-supplement is categorized as highly feasible, with scores of 95.50% (material), 95.21% (media), and 95.83% (language). Teacher response results reached 91.66%, while student responses in small-scale and large-scale trials reached 97.34% and 98.62%, respectively. These findings show that the local culture-based science e-supplement is easy to use, engaging, and helps improve conceptual understanding. Therefore, the e-supplement is suitable to be used as supplementary teaching material in science learning.
Copyright (c) 2026 Dinno Afriza, Hairida, Eni Mayasari https://creativecommons.org/licenses/by/4.0