Universitas Negeri Manado, Jurusan Kimia: Open Journal Systems
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Pengaruh Metode Eksperimen Menggunakan Model Problem Based Learning (PBL) Terhadap Hasil Belajar Siswa Pada Materi Larutan Elektrolit dan Non Elektrolit
Get PDFThis research is limited to the pronlem of the effect of experimental method using the problem based learning model which aims to find out wheather there is an effect of the experimental method using the problem based learning model on the average student learning outcomes on electrolyte and non elsctrolyte solution. This research is the experimental research conducted in X class of MIA MAN 1 Bitung in the academic year 2019/2020, and uses two classes namely class X MIA 1 as an experimental class and class X MIA 2 as an control class. The results of research in the experimental class given the experimental method used the problem based learning model obtained an averaged value of 89,2 while for the control class that was only given the experimental method obtained an averaged value of 50,6. For testing the hypothesis obtained thad H1 is accepted so it can be stated that the average student learning outcomes applied by the experimental method used the problem based learning model are higher than those using only the experimental methodTujuan penelitian ini untuk mengetahui apakah terdapat pengaruh metode eksperimen menggunakan model Problem Based Learning (PBL) terhadap rata-rata hasil belajar siswa pada materi larutan elektrolit dan non elektroli.. Penelitian ini merupakan penelitian eksperimen yang dilakukan di kelas X MIA MAN 1 Bitung pada tahun ajaran ajaran 2019/2020, dan menggunakan dua kelas yaitu kelas X MIA 1 sebagai kelas eksprimen dan kelas X MIA 2 sebagai kelas kontrol. Untuk hasil penelitian pada kelas eksperimen yang diberikan metode eksperimen menggunakan model Problem Based Learning (PBL) diperoleh nilai rata-rata 89,2 sedangkan untuk kelas kontrol yang hanya diberikan metode eksperimen memperoleh nilai rata-rata 50,6. Untuk pengujian hipotesis yang diperoleh yaitu H1 diterima sehingga dapat dinyatakan bahwa rata-rata hasil belajar siswa yang diterapkan metode eksperimen menggunakan Model Problem Based Learning (PBL) lebih tinggi dibandingkan dengan yang hanya menggunakan metode eksperimen saja.
Pengaruh Model Pembelajaran Anchored Instruction terhadap Hasil Belajar Siswa
Get PDFThis research is an experimental study using the Anchored Instruction learning model. This study aims to determine the effect of the Anchored Instruction learning model on student learning outcomes on the mole concept subject. This research was conducted in class X SMA Negeri 2 Siau Timur with a sample of 40 people. The research design used was a pre-test and randomized two group design. The experimental class uses the Anchored Instruction learning model and the control class uses the conventional learning model. Analysis of the hypothesis test using t-test with a significant level α = 0.05. The test results obtained indicate that the results of tcount> ttable or 2.112> 2.024, thus H0 is rejected and H1 is accepted, this shows that there is a significant difference between the average value of the initial test (posttest) of the experimental group and the control group. So it can be concluded that there is a difference between student learning outcomes using the Anchored Instruction learning model and student learning outcomes using conventional learning models on mole concept subject.Penelitian ini merupakan penelitian eksperimen model pembelajaran Anchored Instruction. Penelitian ini bertujuan untuk mengetahui pengaruh model pembelajaran Anchored Instruction terhadap hasil belajar siswa pada materi konsep mol.. Penelitian ini dilaksanakan di kelas X SMA Negeri 2 Siau Timur dengan jumlah sampel 40 orang. Rancangan penelitian yang digunakan adalah pre-test And Poss-test Randomized Two group design. Kelas eksperimen menggunakan model pembelajaran Anchored Instruction dan kelas kontrol menggunakan model pembelajaran konvensional. Analisis uji hipotesis menggunakan uji-t dengan taraf signifikan α = 0,05. Hasil pengujian yang diperoleh menunjukan bahwa hasil thitung > ttabel atau 2,112 > 2,024, dengan demikian H0 ditolak dan H1 diterima, hal ini menunjukan bahwa terdapat perbedaan signifikan antara rata-rata nilai tes awal (posttest) kelompok eksperimen dan kelompok kontrol. Sehingga dapat disimpulkan bahwa terdapat perbedaan antara hasil belajar siswa yang menggunakan model pembelajaran Anchored Instruction dengan hasil belajar siswa yang menggunakan model pembelajaran konvensional pada materi konsep mol
Sintesis dan Karakterisasi Nanopartikel Zn Menggunakan Kitosan Sebagai Reduktor
Get PDFZn nanoparticles is a material that is widely used in the pharmaceutical and cosmetic industry, as a sunscreen, skin whitening, and anti-aging. The aim of the research was to synthesize Zn nanoparticles using chitosan as a stabilizer by chemical reduction method and determine the effect of chitosan amount on the stability of Zn nanoparticles. This research, the raw material used is shrimp shell powder and then processed in several stages, eliminating proteins, demineralization, and deacetylation. Chitosan obtained is 22,8 % of shrimp shell powder, with a degree of deacetylation is 85 %. Chitosan was used to synthesize Zn nanoparticles as a reducing agent of Zn ions in the ZnO solution and was expected to be a stabilizer. The measurement using Atomic Absorption Spectroscopy (AAS) shows that the concentrate of Zn in solution synthesis result of 13,88 mg/l, based on the UV-Vis spectrophotometry obtained maximum wavelength of 355,71 nm and absorbance of 0,062, the shapes of the nanoparticles obtained tend to aggregate. Based on measurements by Particle Size Analyzer (PSA) which has been synthesized Zn nanoparticles have the average size of the particles in the sample is 213,41 nm. 
Penghambatan Reaksi Maillard dari Ekstrak Buah Pisang Goroho Putih (Musa acuminata Colla) Sebagai Pencegahan Diabetes Mellitus
Get PDFIndonesian natural products that are antioxidant have diversity and have not been used optimally, one of which is white goroho banana. White goroho banana (Musa acuminate Colla) is one of the endemic plants originating from North Sulawesi. These bananas are often used empirically as an additional / main food for people suffering from diabetes mellitus. This research aims to determine the potential inhibition of the Maillard reaction from extracts of white goroho banana by measuring the carbonyl protein content using a spectrophotometer. The result of this research is white goroho banana can used as inhibitor Maillard reaction to restrain Diabetes mellitus surface and grow. Acetone extract has the highest inhibitor Maillard reaction than ethanol and methanol. The activity of inhibitor Maillard reaction from acetone, ethanol and methanol extracts are 5,49; 3,18; 2,96%.Indonesian natural products that are antioxidant have diversity and have not been used optimally, one of which is white goroho banana. White goroho banana (Musa acuminate Colla) is one of the endemic plants originating from North Sulawesi. These bananas are often used empirically as an additional / main food for people suffering from diabetes mellitus. This research aims to determine the potential inhibition of the Maillard reaction from extracts of white goroho banana by measuring the carbonyl protein content using a spectrophotometer. The result of this research is white goroho banana can used as inhibitor Maillard reaction to restrain Diabetes mellitus surface and grow. Acetone extract has the highest inhibitor Maillard reaction than ethanol and methanol. The activity of inhibitor Maillard reaction from acetone, ethanol and methanol extracts are 5,49; 3,18; 2,96%.Produk alam Indonesia yang bersifat antioksidan sangatlah berlimpah dan belum dimanfaatkan secara optimal, salah satunya adalah pisang goroho putih (Musa acuminata Colla). Pisang goroho putih (Musa acuminate Colla) merupakan salah satu tanaman endemik yang berasal dari Sulawesi Utara. Pisang ini sering digunakan secara empiris sebagai makanan tambahan/ pokok bagi orang yang menderita penyakit diabetes mellitus. Penelitian ini bertujuan untuk menentukan potensi penghambatan reaksi Maillard dari ekstrak buah pisang goroho putih dengan mengukur kandungan protein karbonil menggunakan spektrofotometer. Dari penelitian ini diperolah hasil bahwa ekstrak buah pisang goroho putih dapat berperan sebagai penghambat (inhibitor) reaksi Maillard untuk mencegah timbul dan berkembangnya penyakit diabetes mellitus. Ekstrak aseton memiliki aktivitas penghambat reaksi Maillard tertinggi dibandingkan ekstrak etanol dan metanol. Aktivitas penghambatan reaksi Maillard dari ekstrak aseton, etanol dan metanol berturut-turut adalah 5,49; 3,18; 2,96 %
Nanocoating Polifenol Sebagai Bahan Pengawet Alami pada Buah-Buahan
Get PDFUtilization of natural ingredients as a means of supporting health has actually been applied by humans for a long time, especially green tea plants (Camellia sinensis). The high polyphenol content in green tea is used to kill harmful bacteria and also bacteria that cause disease in the oral cavity. This study aims to determine how to optimize the extraction of polyphenols from green tea to produce a large polyphenol extract so that it can be used as an ingredient for edible coating formulations with carrageenan and chitosan as well as to determine the preservation ability of the polyphenol edible coating formulations with carrageenan and chitosan to be used for preservation fruits. The stages of this research include: extraction, characterization, polyphenol content analysis, microbial inhibition test and edible coating formulation. The results of the analysis of the total polyphenol content obtained an average of two tests of 22.05% and in the microbial inhibition test, the optimum concentration of polyphenol extract as an antimicrobial was 0.5%. The most effective edible coating formulations with carrageenan and chitosan for tomatoes are polyphenols 0.1%; 0.25%; 0.5%, chitosan-polyphenols 0.5%, and carrageenan-polyphenols 0.25% and caragenan-polyphenols 0.5%. While the most effective coating formulation for grapes is 0.5% polyphenols.Pemanfaatan bahan-bahan alami sebagai sarana penunjang kesehatan sebenarnya telah diterapkan oleh manusia sejak lama, terutama tanaman teh hijau (Camellia sinensis). Kandungan polifenol yang tinggi dalam teh hijau dimanfaatkan untuk membunuh bakteri-bakteri perusak dan juga bakteri yang menyebabkan penyakit di rongga mulut. Penelitian ini bertujuan untuk mengetahui cara optimasi ekstraksi polifenol dari teh hijau agar dihasilkan ekstrak polifenol yang besar sehingga dapat dimanfaatkan sebagai bahan untuk formulasi edible coating dengan karagenan dan kitosan serta untuk mengetahui kemampuan pengawetan dari formulasi edible coating polifenol dengan karagenan dan kitosan agar dapat dimanfaatkan untuk pengawetan buah-buahan. Tahapan penelitian ini meliputi: ekstraksi, karakterisasi, analisis kandungan polifenol, uji daya hambat mikroba dan formulasi edible coating. Hasil analisis kandungan total polifenolnya didapatkan hasil rata-rata dua pengujian sebesar 22,05% dan pada uji daya hambat mikroba, konsentrasi ekstrak polifenol yang optimum sebagai antimikroba adalah 0,5%. Hasil formulasi edible coating dengan karagenan dan kitosan yang paling efektif untuk tomat adalah polifenol 0,1%; 0,25%; 0,5%, kitosan-polifenol 0,5%, serta karagenan-polifenol 0,25% dan karagenan-polifenol 0,5%. Sedangkan formulasi coating yang paling efektif untuk buah anggur adalah polifenol 0,5%
Identifikasi gula spesifik pada aglutinin dari rumput laut
Get PDFAgglutinin or lectin is a protein or glycoprotein that binds saccharide specifically. The substance can agglutinate cells, because of the cells surfaces consist of saccha- rides. Halymenia durvillaei, Laurencia obtusa and Ulva fasciata, contain agglutinin. Cells agglutination by agglutinin can be inhibited by specific saccharide which is its specific sugar. This research aims to determine the specific sugar of agglutinin from Halymenia durvil laei, Laurencia obtusa and Ulva fasciata seaweeds. The researched shows that specific sugar on agglutinin of Laurencia obtusa is D-Glucosamine, and Ulva fasciata is D(+)-Glucose.Aglutinin atau lektin adalah protein atau glikoprotein yang mengikat gula secara spesifik. Substans tersebut dapat mengaglutinasi sel karena permukaan sel terdiri atas gula atau sakarida. Halymenia durvillaei, Laurencia obtusa dan Ulva fasciata mengandung aglutinin. Aglutinasi sel oleh aglutinin dapat dihambat oleh gula tertentu yang merupakan gula spesifiknya. Penelitian ini bertujuan untuk menentukan jenis gula spesifik pada aglutinin dari rumput laut Halymenia durvillaei, Laurencia obtusa dan Ulva fasciata. Penelitian ini menunjukkan bahwa gula spesifik pada agglutinin dari ekstrak Laurencia obtusa adalah D-glukosamin, dan Ulva fasciata adalah D(+)-Glukosa
Pengaruh Metode Pembelajaran Inquiry Berbasis Visualisasi Materi Larutan Elektrolit dan Nonelektrolit di Kelas X IPA SMA Negeri 1 Kawangkoan
Get PDFThe purpose of this study is to examine the effect of visualization-based inquiry learning methods on student learning outcomes in electrolyte and non-electrolyte solution material. This research was conducted in Kawangkoan 1 Public High School, in the even semester X IPA students, 2018/2019 academic year. Class X IPA students 1 (n = 31) as the experimental class and class X IPA 2 (n = 32) as the control class. The test used in this study statistical t test with significance level α = 0.05 with the testing criteriat> ttable then H0 is rejected and H1 accepted. The results obtained in this test obtained tcount 5.25> ttable 1.670. This test is done not to improve student learning outcomes beyond the minimum standard of completeness criteria in school but this testing is only to see the effect of visualization based inquiry learning methods on student learning outcomes. Based on the results obtained it can be concluded that there are differences in student learning outcomes applied with conventional learning models (control class) and visualization based inquiry learning methods (experimental class)Pelaksanaan penelitian ini bertujuan untuk mengkaji pengaruh metode pembelajaran inquiry berbasis visualisasi terhadap hasil belajar siswa pada materi larutan elektrolit dan nonelektrolit. Penelitian ini dilaksanakan di SMA Negeri 1 Kawangkoan, pada siswa kelas X IPA semester genap, tahun akademik 2018/2019. Siswa kelas X IPA 1 (n=31) sebagai kelas eksperimen dan siswa kelas X IPA 2 (n=32) sebagai kelas kontrol. Pengujian dalam penelitian ini digunakan statistik uji t dengan taraf nyata α = 0,05 dengan kriteria pengujian thitung > ttabel maka H0 ditolak dan H1 diterima. Hasil yang di dapatkan pada pengujian ini diperoleh thitung 5,25 > ttabel 1,670. Berdarkan hasil yang diperoleh dapat disimpulkan bahwa terdapat perbedaan hasil belajar siswa yang diterapkan dengan model pembelajaran konvensional (kelas kontrol) dan metode pembelajaran inquiry berbasis visualisasi (kelas eksperimen
Penghambatan Oksidasi Lipid Minyak Ikan Cakalang (Katsuwonus pelamis) Oleh Air Jahe (Zingiber officinale var. rubrum) Selama Penyimpanan Dingin
Get PDFFish is one of the main foods for humans that are rich of proteins, fatty, and minerals that are good for health. Unsaturated fatty acids are very easily oxidized by the presence of catalysts such as oxygen, heat, light, and the presence of metals. Ginger contains antioxidants which can inhibit oxidation of fat or oil. This study aims to inhibit fat oxidation of skipjack fish with the addition of ginger. Skipjack fish soaked in ginger water with a concentration of 10%, 20%, 30% and the control, then saved for 0, 2, 4 days. The fish was extracted by the wet rendering method and then analyzed with 2 parameters, peroxide value and free fatty acids with the titration method. The best concentration in inhibiting lipid oxidation of skipjack fish is at a concentration of 10% and 30%. The peroxide value of cakalang oils is still below the IFOS standard of 3.75 meq O2/kg and the percentage of free fatty acids is still below the standard of 1.5
Efektivitas Strategi REACT Terhadap Hasil belajar Siswa Pada Materi Larutan Penyangga Di Kelas XI SMA Negeri 2 Langowan
No full textChemistry is a science that studies materials that are generally abstract in nature so many students find it difficult to understand the concept of chemistry which causes a lack of interaction between real life and chemical knowledge. This study aims to determine the effectiveness of the REACT strategy in improving student learning outcomes in buffering material at SMA Negeri 2 Langowan. The research method used is Quasi Experiment Design with research design is Posttest-only Control Group Design. The population is all students of class XI Science in SMA Negeri 2 Langowan even semester 2017/2018. The sample of this study were all students of class XI IPA 1, amounting to 25 people as the experimental class and all students of class XI IPA 2, amounting to 21 people as the control class. Data collected is processed from the results of Posttest. Data were analyzed using the Independent t-test formula to test the research hypotheses and obtained tcount> ttable (7.99> 2.02), so it can be concluded that the Contextual Teaching and Learning (CTL) learning method with REACT strategy proved to be effective against improving student learning outcomes in buffer material in class XI IPA of SMA Negeri 2 Langowan.Kimia merupakan ilmu sains yang mempelajari materi-materi yang umumnya bersifat abstrak sehingga banyak siswa sulit memahami konsep ilmu kimia yang menyebabkan kurangnya interaksi antara kehidupan nyata dan pengetahuan kimia. Penelitian ini bertujuan untuk mengetahui efektivitas strategi REACT dalam meningkatkan hasil belajar siswa pada materi larutan penyangga di SMA Negeri 2 Langowan. Metode penelitian yang digunakan yaitu Quasi Experiment Design dengan desain penelitian Posttest-only Control Group Design. Populasinya yaitu seluruh siswa kelas XI IPA di SMA Negeri 2 Langowan semester genap tahun ajaran 2017/2018. Sampel penelitian ini adalah seluruh siswa kelas XI IPA 1 yang berjumlah 25 orang sebagai kelas eksperimen dan seluruh siswa kelas XI IPA 2 yang berjumlah 21 orang sebagai kelas kontrol. Data yang dikumpulkan diolah dari hasil Posttest. Data dianalisis dengan menggunakan rumus Independen t-test untuk menguji hipotesis penelitian dan diperoleh thitung>ttabel (7,99>2,02), sehingga dapat disimpulkan bahwa metode pembelajaran Contextual Teaching and Learning (CTL) dengan strategi REACT terbukti efektif terhadap peningkatan hasil belajar siswa pada materi larutan penyangga di kelas XI IPA SMA Negeri 2 Langowan
Pengaruh Metode Pembelajaran Mind Mapping terhadap Hasil Belajar pada Pokok Bahasan Hukum-Hukum Dasar Kimia Siswa Kelas X Semester Ganjil di SMA Negeri 2 Langowan
Get PDFThis research aims to determine the effect of mind mapping learning methods on the basic laws of chemistry toward learning outcomes of students of class X MIPA in SMA Negeri 2 Langowan. The sample used in this study were all students of class X MIPA of SMA Negeri 2 Langowan. This research uses an experimental method, with the research method used is Quasi Experiment with Nonequivalent Control Group Design design. The research data were obtained from post-test results. Obtained the average value of student learning outcomes Experiment class is 85. The results showed the value of tcount = 15.7> ttable = 2.21, so H0 was rejected and H1 was accepted. Based on the results of the research it can be concluded that there is an influence on student learning outcomes on the basic laws of chemistry using mind mapping learning methods.Penelitian ini bertujuan untuk mengetahui pengaruh metode pembelajaran mind mapping pada materi hukum-hukum dasar kimia terhadap hasil belajar siswa kelas X MIPA di SMA Negeri 2 Langowan. Sampel yang digunakan dalam penelitian ini adalah seluruh siswa kelas X MIPA SMA Negeri 2 Langowan. Penelitian ini menggunakan metode eksperimen, dengan Metode penelitian yang digunakan yaitu Quasi Experimen Design dengan desain penelitian Nonequivalent Control Group Design. Data penelitian diperoleh dari hasil post-test. Diperoleh rata-rata nilai hasil belajar siswa kelas Eksperimen adalah 85. Hasil penelitian menunjukkan nilai thitung = 15,7 > ttabel = 2,21, sehingga H0 ditolak dan H1 diterima. Berdasarkan hasil penelitian dapat disimpulkan bahwa terdapat pengaruh terhadap hasil belajar siswa pada materi hukum-hukum dasar kimia dengan menggunakan metode pembelajaran mind mapping