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All Journal Jurnal Ilmu Dasar Jurnal Matematika & Sains PROSIDING SEMINAR KIMIA Jurnal Inovasi Pembelajaran Kimia (Journal Of Innovation in Chemistry Education) Indonesian Journal of Chemical Science and Technology Educenter: Jurnal Ilmiah Pendidikan
Marham Sitorus
Program S3 Ilmu Kimia PPs UNAND Kampus Limau Manis Padang
Biochemistry, Genetics & Molecular Biology Chemical Engineering, Chemistry & Bioengineering Chemistry Control & Systems Engineering Education Energy Materials Science & Nanotechnology Mathematics Social Sciences

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Isomerisasi Linoleat dalam Minyak Jarak Hasil Dehidrasi Menjadi Linoleat Terkonjugasi dan Pemisahannya dengan Kromatografi Kolom Fasa Diam Silika Gel yang Diimpregnasi Perak Nitrat Marham Sitorus; Sanusi Ibrahim; Hazli Nurdin; Djaswir Darwis
Jurnal Matematika & Sains Vol 16, No 1 (2011)
Publisher : Institut Teknologi Bandung

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Abstract

The main component of dehydrated castor oil (DCO) is linoleic and conjugated linoleic acid (CLA) as triglyseride forms.  This research aim is to find out suitable method for linoleic isomerization of DCO into CLA. Isomerization method must be made chemoselective in order to prevent safonification and transesterification. Isomerization method with 2M NaOH in n-butanol, 1% KOH (w/v) without solvent and irradiated by microwave with iodine as an initiator were tested respectively. CLA was seperated by using column chromatography that AgNO3 impregnated silica gel as a stationary phase. Seperation was based on the differences of coordination bond strenght between the double bond and silver ion. Its  the more unsaturation and trans isomer the more srongly the molecule is retained. Gradient elution was carried out by various ratio of hexane and acetone (v/v) e. g : 97.5 : 2.5, 95 : 5, 90 : 10, 80 : 20, 70 : 30 and  60: 40 with  8 x 5 mL. Each of fraction was analyzed by using TLC and the spot detection was made by UV lamp. The results was  analyzed by using GC, FTIR, UV and GC - MS and Its compared with the standard data. The best isomerization  was  conducted  by microwave irradiated using iodine as an initiator with a conversion factor of 1.97 %.  Seperation of CLA could be made by column chromatography that AgNO3 impregnated silica gel as a stationary phase. The best result  was conducted by eluting with 95: 5 (v/v) of hexane-acetone. The compositions of seperated  were:  0,91% (9c-2c) linoleic, 43.59% (9c/t-12t/c) linoleic, 18.58% (9c/t-1t/c)CLA, 3.46% (9t-11t) linoleic, 19.19%(9t- 1t) CLA and 0.86% ricinoleic.  The ratio of CLA : linoleic prepared was  0.77 : 1 or 70, 32 % compared to the standar with the proportions of 1.45:1.
PERBEDAAN HASIL BELAJAR SISWA PADA MATERI REAKSI REDOKS MENGGUNAKAN MODEL PEMBELAJARAN KOOPERATIF TIPE TEAM GAMES TOURNAMENT BERBASIS MEDIA KARTU SOAL DAN ULAR TANGGA Ester Hartina Ria Sinaga; Manihar Situmorang; Marham Sitorus
PROSIDING SEMINAR KIMIA 2021: SEMINAR NASIONAL KIMIA 2021
Publisher : PROSIDING SEMINAR KIMIA

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Penelitian ini bertujuan untuk mengetahui perbedaan penerapan model kooperatif tipe Teams Games Tournament (TGT) berbasis media kartu soal dan ular tangga pada materi reaksi redoks di kelas X SMA Negeri 14 Medan. Sampel penelitian sebanyak dua kelas, yaitu kelas eksperimen I diberi perlakuan menggunakan media ular tangga dan kelas ekperimen II diberi perlakuan menggunakan media kartu soal. Penelitian ini merupakan penelitian Pretest-postest Control Group Design. Penelitian ini meggunakan instrument test yang telah diujicobakan dan telah valid. Data hasil belajar siswa di uji coba normalitas dan homogenitasnnya, hasil yang didapat kedua sampel berdistribusi normal dan berdistribusi homogen. Uji hipotesis dilakukan dengan menggunakan uji t- dua pihak dengan hasil penelitian ini pada taraf signifikansi 5% ( menunjukkan bahwa ) maka Ho ditolak. Hal ini menunjukkan bahwa adanya perbedaan hasil belajar menggunakan pembelajaran model model kooperatif tipe Teams Games Tournament (TGT) berbasis kartu soal dan ular tangga pada materi redoks. Kata Kunci: Penuntun praktikum, pengembangan dan sistem koloid .
Study of Dehydration of Ricinoleic of Castor Oil By P2O5 Marham Sitorus; Sanusi Ibrahim; Hazli Nurdin; Djaswir Darwin
Jurnal ILMU DASAR Vol 12 No 2 (2011)
Publisher : Fakultas Matematika dan Ilmu Pengetahuan Alam Universitas Jember

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Abstract

The aim of this research is to find out the best temperature, time and amount of dehydrator on dehyration of ricinoleic of castor oil by P2O5. Dehydration as means to obtain linoleic and CLA (conjugated linoleic acid) as glyseride forms. Dehydration was carried out using various temperature, time and amount of dehydrator. The reaction medium was maintained under vacuum through by silica gel to reduced water, gentle bubling with nitrogen thorough by Mg to prevent oxidation, and used Zn powder as an antipolymerization agent. Dehydration was followed by GC which the best result was caused the lowest ricinoleic and the highets linoleic and CLA. Identification was done by FTIR, UV and GC- MS and it was compared with the standard. The best dehydration was obtain for 200oC, 3% (w/w) P2O5, and 4 h with a convertion factor (yield) of 97,94%. The composition of best result was: 1.02% (9c – 12c) linoleic, 41.97% (9c/t – 12t/c) linoleic, 19.50% (9c/t-12t/c) CLA, 4.89% (9t – 12t)linoleic,19.79%(9t–11t)CLA and0.94%ricinoleic.TheratioofCLA:linoleicofdehydrated was 0.82 : 1 or 76.18 % compared to the standard CLA with the proportions of 1.45:1.
PENGARUH TEKNOLOGI IT PADA MODEL PEMBELAJARAN DISCOVERY CONSTRUCTIVE LEARNING UNTUK MENINGKATKAN PEMAHAMAN SISWA MENGENAI ZAT ADITIF MAKANAN DI KELAS VIII SMP KALAM KUDUS MEDAN Neva Asih Sary Silalahi; Ida Duma Riris; Marham Sitorus
PROSIDING SEMINAR KIMIA Vol 1 No 2 (2023): Prosiding SNKT II 2022
Publisher : Jurusan Kimia Fakultas Matematika dan Ilmu Pengetahuan Alam Universitas Mulawarman

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This research aims for knowing is there is difference enhancement results study chemistry SMP Kalam Kudus Medan using flash animation media with Ms. Power Point on the Discovery Constructive Learning model. The population in this study were students class VIII-B and VIII-C SMP Kalam Kudus Medan. Taking sample study taken by purposive sampling consisting of from class learning Discovery Constructive Learning with flash animation media and in class learning Discovery Constructive Learning with Ms. Power Point media. Type this research is research experiment pseudo . Based on the results of the data requirements test , it is known that both the result data study student class learning Discovery Constructive Learning with flash animation media and class Discovery Constructive Learning with Ms. Power Point media is stated is normally distributed and has uniform variance (homogeneous) . Based on the normalized gain data , the increase in results learn using _ learning Discovery Constructive Learning with flash animation media is 84.43% and an increase results learn using _ Discovery Constructive Learning with Ms. Power Point media is 71.06 %. The size difference enhancement results study chemical students is 13.37%. Test results hypothesis , obtained t < -t½α and t > t½α by using t test two party namely 0.0437 < -0.025 and 0.0437 > 0.025 at the level significance = 0.025. This means that H0 is rejected and Ha is accepted , where Ha = exists difference enhancement results study chemistry SMP Kalam Kudus Medan using flash animation media with Ms. Power Point on the Discovery Constructive Learning model for class VIII SMP Kalam Kudus Medan on the subject discussion substance additive food 2013/2014. Keywords: Discovery Constructive Learning model, IT media , SMP Kalam Kudus Medan
Pengembangan E-Modul Kimia Berbasis Proyek pada Materi Larutan Elektrolit dan Non Elektrolit Sihombing, Indah Sari; Marham Sitorus
Educenter : Jurnal Ilmiah Pendidikan Vol. 1 No. 4 (2022): Educenter : Jurnal Ilmiah Pendidikan
Publisher : ARKA INSTITUTE

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.55904/educenter.v1i4.89

Abstract

This study aims to (1) to determine the results of the analysis of chemistry teaching materials on electrolyte and non-electrolyte solution materials used in schools according to BSNP standards, (2) to develop e-modules for electrolyte and non-electrolyte solution materials according to the BSNP eligibility criteria and have been based on projects, and (3) To determine student learning outcomes after being given project-based e-modules. The population in this study were all students of class X MIA SMA Negeri 1 Deli Tua, totaling 6 classes. The sample in this study was class X MIA 5 who was taught with a project-based chemistry e-module. The instrument used is an e-module feasibility questionnaire according to the BSNP standard, a learning outcome test of 20 questions that have been tested valid. This study uses the method and media development (R&D) with the ADDIE model. The ADDIE model has several stages, namely Analysis, Design, Develop, Implementation, and Evaluation. Where the results of the feasibility analysis of the content feasibility aspect of the e-module are 3.82; language eligibility is 3.83; The feasibility of presenting 3.81 and the feasibility of graphics 3.77 means that the teaching materials from the trial are very valid based on the BSNP. The average student learning outcomes who are taught project-based e-modules in one class are 78.8095. The results of the right-hand t-test with t count = 4.147> t table = 2.086. Thus the criteria for testing the hypothesis t count > t table are met. This means that Ho is rejected, Ha is accepted, so it can be concludedthat the project based chemistry learning e-module developed is better in improving students' chemistry learning outcomes in electrolyte and non-electrolyte solution materials.
Influence of Ethnopedagogical Materials and Problem Based Learning on Students Learning Interest and Critical Thinking Ramlan Silaban; Grace Octavia Hutasoit; Tita Linyan Pardede; Ida Duma Riris; Marham Sitorus; Rabiah Afifah Daulay; Rafida Almira Samosir; Irving Josafat Alexander
Jurnal Inovasi Pembelajaran Kimia (Journal of Innovation in Chemistry Education) Vol. 7 No. 1 (2025): APRIL 2025
Publisher : Universitas Negeri Medan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24114/jipk.v7i1.67607

Abstract

The cultural wealth of Indonesia has great potential in chemistry education, but it has not been optimally utilized. Materials such as reaction rates can be contextualized through traditional processes, such as the fermentation of tuak. The lack of relevant teaching materials impacts students' low interest and critical thinking skills. Therefore, an innovation in the form of ethnopedagogy-based Student Worksheets with a Problem Based Learning model is needed to create meaningful learning. This study uses a quantitative approach with a quasi-experimental method. The instruments used consist of 5 essay questions to measure critical thinking skills and a questionnaire containing 20 statements to measure learning interest. A hypothesis test was conducted using a one-tailed Independent Sample T-Test. The results show that the average learning interest of students in the experiment class is higher compared to the control class, namely 90.25 and 85.625, respectively. Meanwhile, the average posttest score for students' critical thinking ability in the experimental class reached 92.25 higher than the control class, which scored 83.5. This shows that the use of Student Worksheet based on ethnopedagogy and Problem Based Learning has an influence on students' learning interest and critical thinking.
Synthesis of Cinnamic Acid from Benzoin Extract Using Sulfuric Acid as a Catalyst Junaldo Andreas Pardede; Marham Sitorus
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.v8i2.68723

Abstract

This study explores the synthesis of cinnamic acid from benzoin extract using sulfuric acid as a catalyst. Benzoin resin was extracted to obtain cinnamyl cinnamate, which was then hydrolyzed under acidic conditions to yield cinnamic acid. The synthesized compound was characterized using Fourier- transform infrared (FTIR) spectroscopy and gas chromatography-mass spectrometry (GC-MS). The FTIR spectra confirmed the presence of characteristic functional groups of cinnamic acid, while GC- MS analysis verified its purity and molecular structure. The optimized reaction conditions provided a significant yield, indicating the efficiency of this method in producing cinnamic acid from a natural source.
Co-Authors Djaswir Darwin Djaswir Darwis Ester Hartina Ria Sinaga Grace Octavia Hutasoit Hazli Nurdin Hazli Nurdin Ida Duma Riris Irving Josafat Alexander Junaldo Andreas Pardede Manihar Situmorang Neva Asih Sary Silalahi Rabiah Afifah Daulay Ramlan Silaban Samosir, Rafidah Almira Sanusi Ibrahim Sihombing, Indah Sari Tita Linyan Pardede