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All Journal Jurnal Pendidikan Kimia Indonesia Jurnal Matematika & Sains Jurnal Penelitian Pendidikan IPA (JPPIPA) Jurnal Akademika Kimia Jurnal SOLMA Indonesian Journal of Chemistry JMM (Jurnal Masyarakat Mandiri) Jurnal Ilmiah Kanderang Tingang Journal of Educational Chemistry (JEC) Patria : Jurnal Pengabdian Kepada Masyarakat Jurnal Riset Pendidikan MIPA Jurnal Abdimas Ilmiah Citra Bakti (JAICB) Mattawang: Jurnal Pengabdian Masyarakat JSEP (Journal of Science Education and Practice) Jurnal Akademika Kimia Jurnal Ilmu Pendidikan Indonesia JIPI (Jurnal IPA dan Pembelajaran IPA) Mitra Sains Jurnal Akademika Kimia Jurnal Pendidikan MIPA Jurnal Abdimas Ilmiah Citra Bakti
Daud Karel Walanda
Pendidikan Kimia FKIP Universitas Tadulako Palu Indonesi 94119
Agriculture, Biological Sciences & Forestry Arts Humanities Biochemistry, Genetics & Molecular Biology Chemical Engineering, Chemistry & Bioengineering Chemistry Computer Science & IT Education Engineering Environmental Science Health Professions Languange, Linguistic, Communication & Media Law, Crime, Criminology & Criminal Justice Materials Science & Nanotechnology Mathematics Physics Public Health Social Sciences Other

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Pembelajaran Direct Instruction Berbasis Animasi Terhadap Konsepsi Siswa Materi Ikatan Kimia Kelas X Sman 1 Dondo Kabupaten Tolitoli Uswatun Hasanah; Daud K Walanda; Siang Tandi Gonggo
Mitra Sains Vol 5 No 1 (2017): Januari
Publisher : Universitas Tadulako

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/mitrasains.v5i1.37

Abstract

Uncomplete assessing of materials abstract in learning of chemistry will lead to students on experiencing misconceptions as a result of the wrong internalization. This study aimed to analyze the positive effect and significance of the direct instruction learning based on animation to wards students’ conceptions of chemical bonding in the Grade X at SMAN 1 Dondo Tolitoli. This study applied a quasi-experimental method with one group pretest-posttest design. Samples were 29 students determined by purposive sampling. The independent variable in this studywas the direct instruction learning, while the dependent variable was the students' conceptions. The data acquisition instrument was in the form of a diagnostic test consisted of 20 multiple-choice questions and reasons using Certainty of Response Index (CRI). Data was analyzed using t-test two sample pairs. Hypothesis test results obtained –taccount (-16.37) <-ttable (-2.05) at significance level of 5%. This study concluded that there is a significant effect positively of direct instruction learning based onanimation to improvestudents’ conceptions in the Grade X at SMAN 1 Dondo Tolitoli, with the effect size d = 2.8 or with a relatively large level of effectiveness.
Analysis of Vitamin C and Calcium in Jongi Fruits (Dillenia serrata Thunb) Based on Their Maturity Level Miryam B. Kalase; Daud K. Walanda; Mery Napitupulu
Jurnal Akademika Kimia Vol. 8 No. 3 (2019)
Publisher : Universitas Tadulako

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/j24775185.2019.v8.i3.pp147-152

Abstract

Jongi plant (Dillenia serrata Thunb) is one of the plants that found  Poso District. The characteristics of this fruit are mainly on the refreshing sour taste and attractive color which is yellow. This study aims to determine the levels of vitamin C and calcium in this fruit based on the level of maturity. The fruit of jongi used as a sample was categorized into there type of maturity namely mature, ripe, and overripe. The method used for vitamin C analysis was iodimetry and for calcium, analysis using spectrophotometry (λ: 422.7 nm). From the results of the analysis, it was obtained that the levels of vitamin C in fruit jongi successively were 81.84, 114.40, and 70.40 mg/100 g, while the calcium levels obtained in the fruits were 5.91, 5.65, and 6.46 mg/100 g. The data above showed that the maximum vitamin C content in jongi fruit when the fruit was in ripe type, while the highest calcium content in jongi fruit was when the fruit in overripe type.
Antioxidant Activity Test of Red Spinach’s Extract (Blitum rubrum) in Ethanol Solvent and Water Solvent with DPPH Nur A. O. Buhang; Siti Nuryanti; Daud K. Walanda
Jurnal Akademika Kimia Vol. 8 No. 3 (2019)
Publisher : Universitas Tadulako

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/j24775185.2019.v8.i3.pp153-159

Abstract

The study of red spinach antioxidants (Blitum rubrum) in two types of solvents i.e ethanol and water has been performed. The purpose of this study was to determine the antioxidant activity of red spinach extract from Tinombo Selatan district, Central Sulawesi. Red spinach was macerated in ethanol and water to obtain variations of extract concentrations of 20, 40, 60, and 80 mg/L. Free radicals used were DPPH reagents while vitamin C was used as a positive control. The measurement of absorbance of red spinach’s extract was conducted by spectrophotometric. The results showed that IC50 extract of red spinach in ethanol and water were 51.404 mg/L and 52.227 mg/L, while the value of IC50 vitamin C in ethanol and water solvent was 43.241 mg/L and 140.507 mg/L. Based on the IC50 red spinach’s extract in ethanol and water have strong antioxidant activity.
Phytochemical Screening and Antioxidant Activity Test of Red Onion (Allium ascolinicum L.) Extract Variety of Palu Valley Rimah Juwita; Daud K. Walanda; Supriadi Supriadi
Jurnal Akademika Kimia Vol. 9 No. 2 (2020)
Publisher : Universitas Tadulako

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/j24775185.2020.v9.i2.pp63-69

Abstract

The red onion of Palu valley variety is a plant that is widely found in Palu area and regarded as a leading commodity in Central Sulawesi. The purpose of this study was to examine the secondary metabolite compounds contained in red onion (Allium ascolinicum L.) of Palu valley variety and its antioxidant activity. Antioxidant activity test in this study used DPPH (1,1-Diphenyl-2-Pikrilhidrazil) as a source of free radical, and vitamin C as the comparison. The antioxidant activity of red onion extract was analyzed using a UV-Vis spectrophotometer. The red onion tuber powder was extracted by maceration using ethanol solvent. Qualitative test of onion powder showed positive results on alkaloids, flavonoids, and tannin compounds. The samples and vitamin C were tested for antioxidant activity in various extract concentrations of 10, 30, 50, 70, and 90 ppm. The results showed that red onion extract of Palu valley variety presented an IC50 value of 38.548 ppm, and vitamin C presented an IC50 value of 22.646 ppm. Based on these values, the red onion (Allium ascolinicum L.) extract is categorized as a very strong class of antioxidant which can be used as a source of natural antioxidant.
Analysis of Macro Nutrient on Rono Fish (Xenopoecilus oophorus) Freshwater Delviana Melego; Mery Napitupulu; Daud K. Walanda
Jurnal Akademika Kimia Vol. 8 No. 4 (2019)
Publisher : Universitas Tadulako

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/j24775185.2019.v8.i4.pp191-196

Abstract

Fish are assumed to have high nutritional value with mineral content, vitamins, fats, and proteins containing essential amino acids that are needed for growth and human intelligence. One type of them is rono fish (Xenopoecilus oophorus) freshwater which is an endemic fish that comes from lake Poso, Central Sulawesi and still found in traditional markets of Tentena city, but the local community is less interested in this type of fish and the lack of literature that informs about the nutritional content of rono fish. The research aims to determine the macronutrient content in rono fish. The nutrient content analyzed in fish was on carbohydrates, proteins, and fats by using the anthrone sulfate method for carbohydrate analysis, Kjeldahl method for protein, and for fat analysis using the soxhlet method. The results of the analysis obtained that macronutrient in freshwater rono fish was followed carbohydrate was 9.26%, the protein was 37.79% and fat was 11.92%.
The Effect of Copper(II) and Cadmium(II) Ions Against the Percent Mercury Ion Extraction Using Emulsion Liquid Membrane Technique Suhartini Musa; Baharuddin Hamzah; Daud K. Walanda
Jurnal Akademika Kimia Vol. 8 No. 4 (2019)
Publisher : Universitas Tadulako

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/j24775185.2019.v8.i4.pp218-222

Abstract

The effect of copper(II) and cadmium(II) ions on the percent of mercury ion extraction using an emulsion liquid membrane technique have been performed. This study used HNO3 as an internal phase, mixed span 80 and span 20 as a surfactant, benzoyl acetone as cation carrier, kerosene as membrane phase, and mercury solution as a sample solution. Variations of concentrations of copper(II) and cadmium(II) ions added were 10, 20, and 30 ppm with mercury concentrations of 30 ppm. The result of the research showed that the addition of copper(II) ion with concentrations of 10 to 30 ppm decreased the percentage of mercury ion extraction 30 ppm by 12.12% and the addition of cadmium(II) ion with the concentration of 10 to 30 ppm decreased the percentage of mercury ion extraction 30 ppm by 11.74%.
Effectiveness of Google Classroom in Chemistry Learning on Stoichiometry Topic Viewed from Students’ Learning Motivation Emi Sulmeni; Daud K. Walanda
Jurnal Akademika Kimia Vol. 9 No. 4 (2020)
Publisher : Universitas Tadulako

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/j24775185.2020.v9.i4.pp199-204

Abstract

This study aimed to determine the effectiveness of using google classroom in chemistry learning in terms of student learning motivation in MAN 2 Parigi, Sulawesi Tengah Indonesia. The sample in this study was students in class X MIA 2 (n = 23). The data analysis technique was the effect size d Cohen test, the value was 0.86 which had a very large effect category. This influence can be seen from students' learning motivation which increased with an average score of 3.70 which had a very good category. Based on these data it can be concluded that Google classroom affected the students’ learning results and learning motivation.
Application of Clove Leaf Oil (Syzygium aromaticum L.) on Preservation of Milkfish (Chanos chanos) Rukmawati Rukmawati; Daud K. Walanda; Irwan Said
Jurnal Akademika Kimia Vol. 10 No. 4 (2021)
Publisher : Universitas Tadulako

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/j24775185.2021.v10.i4.pp218-223

Abstract

Clove leaf oil (Syzygium aromaticum L.) is obtained from distilling clove leaves. This study aimed to examine the effect of clove leaf oil on the preservation of milkfish meat. Clove leaf oil was obtained by steam distillation and purified by a simple distillation method. The number of microbes was determined using the total plate count (TPC) method, while the organoleptic test used a level of preference for color, smell, texture, and taste. The results showed that the pH and the number of fish meat bacteria at a concentration of 8%, when left for one day, were 6.61 and 2.46 × 10-7 CFU/mL, while the three days was 7.2 and 2.98 × 10-7 CFU/mL, a concentration of 10% in 1 day which was 6.64 and 2.03×10-7 CFU/mL while the three days was 7.25 and 2.54 × 10-7 CFU/mL and a concentration of 12 % in 1 day was 6.67 and 1.83 × 10-7 CFU/mL while three days was 7.57 and 2.07 × 10-7 CFU/mL, besides that from organoleptic test data the panelist preference rate was more significant in the concentration of 12 % then the concentration of 10  and 8 %, respectively. The results showed that at a concentration of 12%, it was a good concentration to be used as preservation compared to a concentration of 10 % and a concentration of 8%, both for a 1-day and a 3-days. This shows that the higher the concentration of clove leaf oil, the greater the ability to preserve fish meat.
Determination of Vitamin C and Metal Copper (Cu) Levels in Katokkon Chili (Capsicum chinense Jacq) Based on Maturity Level Novianti Patiung; Daud K. Walanda; Sitti Aminah
Jurnal Akademika Kimia Vol. 10 No. 3 (2021)
Publisher : Universitas Tadulako

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/j24775185.2021.v10.i3.pp182-187

Abstract

Katokkon chili is one type of chili grown mainly in the Tana Toraja district, and the people use this plant as a typical spice with variations colors from green, orange, and red. It is assumed that the plant is rich in vitamins and minerals. This study aims to determine the levels of vitamin C and copper metals in katokkon chili based on their level of maturity. Vitamin C and copper levels were determined by spectrophotometry. The results showed that the highest level of vitamin C was 23.52 and 5.12 mg/kg in both wet and dry orange chilies, while the highest copper level was found in green chili was 12.25 mg/kg
The Extraction of Nickel from Morowali Laterite Ore with Nitric Acid I W. A. Wirawan; Daud K. Walanda; Mery Napitupulu
Jurnal Akademika Kimia Vol. 11 No. 2 (2022)
Publisher : Universitas Tadulako

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/j24775185.2022.v11.i2.pp91-95

Abstract

Nickel extraction from Morowali laterite ore has been carried out with nitric acid as the solvent. This study aims to determine the effect of nitric acid concentration, temperature, and stirring time on nickel content in laterite ore originating from Morowali. Morowali laterite seeds were extracted using the leaching method using nitric acid as the solvent with various concentrations of 0.5, 1, and 2, temperatures of 30, 60, and 95, and stirring times of 3, 6, and 12. Taguchi analysis was used in this study to obtain the effect of the three parameters used. The results showed that the optimum conditions were obtained at a concentration of 2 molars nitric acid, a temperature of 95°C, and a stirring time of 12 hours, with a nickel content of 16.469 ppm and a nickel recovery percent of 3.88%.
Co-Authors AA Sudharmawan, AA Afadil Alam Anshary Alep, Boni Alizah, Nur Almahdali, Khafifah Amalia, Maryam Anang Wahid M.Diah Anggraini Anggraini Anggraini, Windi Arwansyah Arwansyah Baharuddin Hamzah Baloga, Hendra Bau Ratu Berlin, I Dewa Gede Darsikin Darsikin Dasi, Alfina D. A. Delviana Melego Detris Poba Dewi, Evie Kurnia Maya Dewijayanti, Putu W. Djahir, Ahmad Rifaldi Djulia Onggo Eka Dewi Ellak I. von Nagy-Felsobuki Emi Sulmeni Enar, Rohmala Finta Amalinda Finta Amalinda Fitriani, Eva Geoffrey A. Lawrance Griffiths, Zoe Hasmawati Hasmawati I Ketut Suada I Komang Jati Purnawan I Komang werdhiana I W. A. Wirawan Irwan Irwan Irwan Said Ismail Ismail Kasmudin Mustapa Kusuma, I Gede Yoga Nata Leonardo Leonardo Marungkil Pasaribu Mery Napitupulu Miryam B. Kalase Mohammad Jamhari Muhammad Agus Muljanto Mustakim, Sartika MUSTAMIN IDRIS Nakazawa, Koyomi Napitupulu*, Mery Napitupulu, Nurasyah D Ni Luh Cicik Fitriani Novianti Patiung Nur A. O. Buhang Nurasyah Dewi Napitupulu Nurdin Rahman Nurhikma, Nurhikma Poba, Detris Podala, Katherina Pongenda, Rudy Christiyanto Purnama Ningsih Putra, Iim E. Rahma, Sri Ratman Ratman Razni, Razni Reny, Reny Rimah Juwita Rita Lefrida Robert C. Burns Rukmawati Rukmawati Ryka Marina Walanda Setiawan, I Ketut Ardi Siang Tandi Gonggo Siang Tandi Gonggo Siti Nuryanti Sitti Aminah Sitti Rahmawati Solfarina, Solfarina Sri Hastuti Virgianti Pulukadang Sri Mulyani Sabang Suciati, Indah Suhartini Musa Supriadi Supriadi Susilawati, Niluh Eka Syamsiar, Syamsiar Tahril Taslima Tiara Maharani, Tiara Tiwow, Vanny M A Trisnawati Trisnawati Tudjuka, Mora Delfita Uswatun Hasanah Wagiman, Saumadin Walanda, Richard Albert Walanda, Ryka M Walanda, Ryka M. Yeyet Sri Rahmi Yuli Nurmayanti Yulianti, Iluh Devi