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The Effect of Computational-Based Learning Media Using the STAD Type Cooperative Model on Student Learning Outcomes and Motivation on the Subject of Intermolecular Forces Nababan, Tiur Maida Br.; Pratiwi, Ledy; Nugraha, Asep Wahyu
International Journal of Research in STEM Education Vol. 5 No. 1 (2023): May Issue
Publisher : Universitas Terbuka

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.33830/ijrse.v5i1.1590

Abstract

This study aims to determine the effect of computational chemistry-based learning media using the STAD type cooperative learning model on student learning outcomes and motivation on the subject of forces between molecules. The population in this study were grade X students in high schools in Medan city which amounted to 7 classes. The samples of this study were students of class X IPA 3 and X IPA 5, each of which amounted to 36 students. The research instruments used were test instruments in the form of 20 multiple choice questions and non-test in the form of 30 statements. The quality of the research instrument was tested using validity, reliability, difficulty level of questions and differentiating power to determine the questions that would be used as instruments in the study. The data analysis technique shows that in the learning outcomes hypothesis test, the t-count> t-table value is 5.03>1.666 and the results of the learning motivation hypothesis test, the t-count> t-table value is 3.12>1.666. This data shows that there is an effect of computational chemistry-based learning media using the STAD type cooperative learning model on student learning outcomes and motivation on the subject of forces between molecules.
Implementation of STEM-Based Inquiry in Learning Fundamental Laws of Chemistry: Students’ Perception and Response Pohan, Lisa; Retno Dwi Suyanti; Asep Wahyu Nugraha; Dwi Pebrianti; Rahmadatina Panjaitan; Selamat Husni Hasibuan
Jurnal Pendidikan IPA Indonesia Vol. 13 No. 3 (2024): September 2024
Publisher : Universitas Negeri Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15294/87cp1c76

Abstract

This research aims to analyze students' perceptions and responses to STEM-based inquiry learning. This research used a quantitative and qualitative survey method. The subjects of this study were 25 first-semester students who took the General Chemistry course in the chemistry education study program. The research instruments used were questionnaires, interviews, and learning observation sheets. Meanwhile, the quantitative technique used is descriptive analysis. Quantitative data analysis found that 72% of students were actively involved in learning when formulating questions and investigations. STEM-based inquiry learning in observing, measuring, and analyzing data helped 72% of students understand the basic laws of chemistry. Most students benefit from STEM-based inquiry learning because this model triggers curiosity, the ability to formulate scientific questions, and the ability to evaluate and utilize information that helps determine experimental procedures. In conclusion, the learning experience using the STEM-based inquiry learning model on the basic laws of chemistry positively impacts students' perceptions and responses.
Synthesis and Characterization of Hexathiosianatoiron(II) [Fe(NCS)6] 4- Complex Compound and Tetrapyridindithiosianatoiron(II) [Fe(NCS)2(Py)4] Complex Compound Febrianti, Fitria; Sutiani, Ani; Jahro, Iis Siti; Nugraha, Asep Wahyu; Fadhila, Nabila Nur
Indonesian Journal of Chemical Science and Technology (IJCST) Vol 7, No 1 (2024): JANUARY 2024
Publisher : Universitas Negeri Medan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24114/ijcst.v7i1.56440

Abstract

This research aims to synthesize and characterize the complex compounds Hexathiocyanatoiron(II) [Fe(NCS)6] 4- and Tetrapyridinedithiocyanatoiron(II) [Fe(NCS)2(Py)4]. The synthesis of these complex compounds was conducted in the Chemistry Laboratory, Faculty of Mathematics and Natural Sciences, Medan State University, while magnetic susceptibility measurements were carried out using the Magnetic Susceptibility Balance (MSB) instrument in the Inorganic Chemistry Laboratory, Bandung Institute of Technology. The complex compound synthesis involved the reaction of Iron(II) sulfate heptahydrate with Potassium thiocyanate and Pyridine compound in a 1:2 and 1:2:4 molar ratio. The synthesis process was conducted through a direct reaction method in a polar solvent. The obtained results include Hexathiocyanatoiron(II) complex compound, [Fe(NCS)6] 4-, which is pale yellow crystalline with a yield of 32.76%, and Tetrapyridinedithiocyanatoiron(II) complex compound, [Fe(NCS)2(Py)4] which is dark purple crystalline with a yield of 52.62%. These compounds exhibit a melting point of 219℃. Magnetic susceptibility measurements using the MSB instrument revealed a magnetic susceptibility of 6.69 BM (paramagnetic) for the Hexathiocyanatoiron(II) complex[Fe(NCS)6] 4-, and a magnetic moment of 5.61 BM (diamagnetic) for the Tetrapyridinedithiocyanatoiron(II ) complex [Fe(NCS)2(Py)4].
Synthesis of Zeolite from Rice Husk Ash Through Hydrothermal Process in Alkaline Condition Jahro, Iis Siti; Nursanni, Banu; Nugraha, Asep Wahyu; Juwitaningsih, Tita; Cindy, Cindy; Amalia, Meisya
Indonesian Journal of Chemical Science and Technology (IJCST) Vol 7, No 2 (2024): JULY 2024
Publisher : Universitas Negeri Medan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24114/ijcst.v7i2.62257

Abstract

People consider rice husks as agricultural waste. In Deliserdang Regency, in one year's period, 12,600 tons of ash are collected from the burning of around 70,000 tons of rice husk. The synthesis of zeolite from ash of rice husks was carried out by starting process of forming sodium silicate and aluminate compounds through the reaction with Al2O3 and NaOH in water on the room temperature for 10 hours. The results of reaction is refluxed at 70 C for 3 hours. After being stored for around 12 hours at room temperature, the reflux process was continued at 120 C for 8 hours. Infrared spectra of zeolite show an infrared absorption band in the area of around 440; 606; 745; and 1007 cm-1 which is the typical infrared absorption of zeolite X. This is supported by the XRD diffractogram with the diffraction peaks at 2 degree of 12.34; 17.51; 21.53; 27.90; 28.50 and 33.22 degrees.
Analysis of the Needs for the Development of Computational Chemistry-Based Learning Media on the Subject of Hydrocarbons Gustiana, Rara; Nugraha, Asep Wahyu; Nurfajriani, Nurfajriani
LAVOISIER: Chemistry Education Journal Vol 3, No 1 (2024): LAVOISIER: Chemistry Education Journal
Publisher : UIN Syekh Ali Hasan Ahmad Addary Padangsidimpuan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24952/lavoisier.v3i1.11537

Abstract

AbstractThis study aims to analyze the needs before developing computational chemistry-based learning media on hydrocarbon materials. This research is classified as development research developed with the ADDIE model. It's just that the stage used in this study is only limited to the analysis stage. Data collection in research is carried out by literature study methods and field studies with research instruments in the form of questionnaires on learning media needs and interviews by teachers. The location of this study is SMA Negeri Modal Bangsa Arun. Based on the results of interviews with chemistry teachers, it was found that learning hydrocarbon material at the high school level requires more effort because students must understand molecular structure, chemical bonds, and atomic structure. This makes students less understanding of concepts microscopically and can also cause misconceptions. Then, the results of the needs analysis show that there are still limited learning media that support microscopic concepts, especially the shape of molecules in 3-D. Based on the results of this study, it can be concluded that it is necessary to develop computational chemistry-based learning media on hydrocarbon materials.
Improving Students™ HOTs-Literacy Abilities Through Making Summaries at The End of Learning Jahro, Iis Siti; Sutiani, Ani; Suryani, Suryani; Nugraha, Asep Wahyu
Jurnal Inovasi Pembelajaran Kimia (Journal of Innovation in Chemistry Education) Vol. 6 No. 1 (2024): APRIL 2024 EDITION
Publisher : Universitas Negeri Medan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24114/jipk.v6i1.57484

Abstract

The reading and writing habits of SMAN 2 Percut Sei Tuan students are relatively low. Therefore, students' literacy and high order thinking abilities are also relatively low. The implementation of scientific literacy-based learning strategies in the form of making summaries at the end of the learning process is expected to improve students' literacy and high order thinking skills. The instruments used are tests in the form of varied multiple choices and essays totaling 8 and 2 questions. The results of data analysis show that students' initial abilities on the 9 of HOTs-Literacy indicators are very low with an average value of 28.49. The summarizing treatment at the end of the learning process succeeded in improving the ability of HOTs-Literacy students in indicators (1) identifying information and data, (2) using information and data, (3) producing explanatory models, (4) distinguishing questions that can be researched scientifically, (5) formulating hypotheses, (6) making predictions, (7) analyzing data, (8) interpreting data, (9) drawing or presenting conclusions, respectively 63.7 ; 66.7; 68.4 ; 64.0 ; 70.9 ; 70.8; 79.2 ; 81.4 and 86.3 %.
Thermodynamic and Kinetic Study of the Reaction Mechanism of Acetylsalicylic Acid Formation Using Computational Chemistry Methods Julina Indah Gewa Sitompul; Roma Sinaga; Asep Wahyu Nugraha
Indonesian Journal of Chemical Science and Technology (IJCST) Vol. 8 No. 2 (2025): JULY 2025
Publisher : Universitas Negeri Medan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24114/ijcst.v8i2.68706

Abstract

Acetylsalicylic acid or aspirin is one of the most widely used non-steroidal anti-inflammatory drugs (NSAIDs) in medicine because of its properties as an analgesic, antipyretic, and antiplatelet. This study aims to examine the thermodynamic and kinetic aspects of the reaction mechanism of aspirin formation from salicylic acid and acetic anhydride using a computational chemistry approach. The method used to determine energy is the computational chemistry method, the theory used is metode Restricted Hartree-Fock (RHF) with a basis set of 3-21G. The calculation results show the formation of energy (ΔE) of the reaction of -1.21 kJ/mol. The magnitude of the activation energy (Ea) from the computational chemistry calculation is 7.95 kJ/mol. The structure of the intermediate was also successfully identified and visualized, supporting a two-stage reaction mechanism with the presence of a transition state
Thermodynamic and Kinetic Study on the Reaction Mechanism of Paracetamol Formation from 4-Aminophenol Using Computational Chemistry Methods Roma Sinaga; Julina Indah Gewa Sitompul; Asep Wahyu Nugraha
Indonesian Journal of Chemical Science and Technology (IJCST) Vol. 8 No. 2 (2025): JULY 2025
Publisher : Universitas Negeri Medan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24114/ijcst.v8i2.68707

Abstract

Paracetamol, also known as acetaminophen, is one of the most widely used drugs worldwide and is included in the WHO Essential Medicines List. The synthesis process of paracetamol is carried out through the acetylation reaction of 4-aminophenol with acetic anhydride, producing paracetamol and acetic acid as a by-product. This study aims to analyze the thermodynamic and kinetic aspects of the paracetamol formation reaction from 4-aminophenol using a computational chemistry approach. Calculations were performed using the Restricted Hartree-Fock (RHF) method with a 3-21G basis set implemented in the NWChem software, while molecular structure visualization was conducted using Jmol and Avogadro. The results show that the energy change (ΔE) is –25.0107 kJ/mol (exothermic). In addition, the activation energy (Ea) required to reach the transition state is recorded at 623.13 kJ/mol.
Computational Study of Fe(II) Complex Compound Structure Prediction with Thiocyanate (SCN-) and Pyridin (C5H5N) Ligands Using the RHF (Restricted Hartree Fock) Vivi Semari Malau; Asep Wahyu Nugraha
Indonesian Journal of Chemical Science and Technology (IJCST) Vol. 8 No. 2 (2025): JULY 2025
Publisher : Universitas Negeri Medan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24114/ijcst.v8i2.68721

Abstract

The formation of Fe(II) complex compounds with thiocyanate (SCN-) as well as pyridin (C5H5N) forms a tetrapyridinditiocyanateobesi(II) complex compound, [Fe(SCN)2(py)4]. The comparison of these complex compounds is still engineering, so the researchers examined the comparison of the structure of stable complex compounds on Fe(II) with thiocyanate and pyridin ligands, by continuing previous research using computational chemistry. Complex compounds that are more stable and the most suitable molecular formula based on computational calculations using RHF hybrid functions and 6- 31G basis sets, geometry optimization of molecules from NWChem version 6.6 and Jmol software version 14.28.29. The energy of the computational calculation using RHF/6-31G for the structure Fe(SCN)2(C₅H₅N)4: -1524.86976182444 KJ/mol; Fe(SCN)3(C₅H₅N)3 structure: -1557.98302881166 KJ/mol; and Fe(SCN)4(C₅H₅N)2 structure: -2083.53616162888 KJ/mol. The change in formation energy indicates that the structure of Fe(SCN)4(C₅H₅N)2 is the most stable. The most suitable molecular formula for the Fe(II) complex compound is [Fe(SCN)4(C₅H₅N)2].
Kinetics Study Addition Reaction for Methyleugenol with Formic Acid to Produce The Methyleugenol Formic Ester as Intermediate Compound of Hypertension Drug Fadhilah, Nabila Nur; Nugraha, Asep Wahyu; Purba, Jamalum; Dibyanti, Ratu Evina
Indonesian Journal of Chemical Science and Technology (IJCST) Vol. 8 No. 2 (2025): JULY 2025
Publisher : Universitas Negeri Medan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24114/ijcst.v8i2.68778

Abstract

The methyl eugenol formic ester is the intermediate formation of the 1-(3,4-dimethoxy phenyl)-2-amino-2-cyano propane compound, a hypertension drug. This study aimed to find the value of the reaction order and study the mechanism of an addition reaction of methyl eugenol with formic acid to produce the methyl eugenol formic ester. Gas chromatography analysis of the residual methyl eugenol determines the reaction order. There are two dominant products in the synthesis of methyl eugenol formic ester, resulting in the formation reaction of methyl eugenol formic predictable in a two-way reaction mechanism. The determination of the energy of the reactants, products, and transition compounds in the formation reaction of methyl eugenol formic ester compound prescribed through computational studies using NWChem 6.0 and visualization using Jmol. The results of the analysis of the data obtained several conclusions: The value of the reaction ordered for methyl eugenol with formic acid is the first order. Based on the computational result shows that the enthalpy change for the reaction product is ΔH(1) = -47,810 KJ/mol and ΔH(2) = -60,545 KJ/mol. The activation energy for both transition compounds is Ea(1) = 163,1937 KJ/mol and Ea(2) = 370,3477 KJ/mol. This fact indicates that the formation of methyl eugenol formic ester compound using the method (1) was more likely than (2). The prediction is based on the determination of Ea with the computational chemistry following the experimental result, which shows the product of (1) more than the product of (2).