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Jurnal Akademika Kimia

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Published by Universitas Tadulako

ISSN : 23026030 EISSN : 24775185 DOI : https://doi.org/10.22487/

Core Subject : Science, Education,

Chemistry Education

Jurnal Akademika Kimia is an electronic open-access journal that aims to publish the latest research results in the area of chemistry education and pure chemistry from academicians, professionals, and other practitioners at all levels of chemistry education. The journal coverage includes the following: current trends of professional chemistry education, educational technology, teacher education, educational science, learning assessment, learning models, and development of learning materials, as well as pure chemistry including organic chemistry, inorganic chemistry, analytical chemistry, physical chemistry, biochemistry and other chemistry fields such as environmental chemistry, that emphasis on a broad description of the general methods and processes for the synthesis, modification, and characterization of chemical materials.

Arjuna Subject : Kimia(semua kategori) - Kimia (Lain-Lain)

Articles 10 Documents

Search results for , issue "Vol. 9 No. 2 (2020)" : 10 Documents clear

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

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.

Determination of Total Flavonoid Contents and Antioxidant Activity of Leucaena Leucocephala Leaves's Extract Taupik Hidayat; Baharuddin Hamzah; Minarni R. Jura
Jurnal Akademika Kimia Vol. 9 No. 2 (2020)
Publisher : Universitas Tadulako

The study of the determination of total flavonoid contents and antioxidant activity of extract of Leucaena leucocephala leaves had been carried out using UV-Vis spectrophotometry method. This study aimed to determine the total flavonoid contents and the antioxidant power of Leucaena leucocephala extract. Extraction of chemical content from Leucaena leucocephala was carried out by the maceration method using absolute ethanol. The total flavonoid contents from the sample extract were taken up for absorption at wavelength 510 nm and 700 nm. The variation of the concentration of Leucaena leucocephala leaves' extract was respectively 20, 40, 60, and 80 ppm. The results of the study showed that the total flavonoid contents of extracts of Leucaena leucocephala leaves was 2.242 g/100 grams. The antioxidant activity of Leucaena leucocephala leaves extract was carried out using DPPH (1,1-diphenyl-2-picrylhydrazine) and the measurement of absorption was at a wavelength of 517 nm, and by varying the sample concentration. Positive control used was vitamin C solution with the same variation of extract's concentration. The results showed that the IC50 values of Leucaena leucocephala leaves extract and vitamin C were 175.388 and 28.907 ppm. Based on the IC50 data it can be stated that the antioxidant vitamin C was stronger than the Leucaena leucocephala leaves extract which was classified as a weak type of natural antioxidant.

Misconception Reduction by Implementing Contextual Teaching and Learning (CTL) Approach on Salt Hydrolysis Material in Grade XI at SMA 1 Palasa Moh. Raisul; Tahril Tahril; Afadil Afadil
Jurnal Akademika Kimia Vol. 9 No. 2 (2020)
Publisher : Universitas Tadulako

Misconception is a conception of someone who is not in accordance with the scientific concept recognized by experts. Student’s who experience misconceptions will make mistakes in understanding concept’s and occur continuously. This study aimed to determine the percentage of reduction of students’ misconception in grade XI SMA 1 Palasa on salt hydrolysis by implementing contextual teaching and learning (CTL) approach. This study was a quantitative descriptive study with the number of samples of 2 classes, that’s Class XI Science A consisted of 22 students, and Class XI Science B consisted of 22 students. The instrument test was a reasoned multiple choice test accompanied by a certainty of response index (CRI) consisting of 20 items. The results showed that the percentages of the average reduction of students’ misconceptions in the class XI science A and in the class XI science B on salt hydrolysis with contextual teaching and learning (CTL) approach were 19.6 and 9.8%, respectively.

The Implementation of Demonstration Method to Students Learning Outcomes and Interests on Colloid Materials at Class XI Science of SMA Negeri 1 Kasimbar Megawati Megawati; Suherman Suherman; Purnama Ningsih
Jurnal Akademika Kimia Vol. 9 No. 2 (2020)
Publisher : Universitas Tadulako

This research aims to examine the demonstration method on chemistry learning through colloid materials to learning achievement and interest of students at class XI Science of SMA Negeri 1 Kasimbar. This research was a true experimental design with pretest-posttest control group design. Sampling was carried out based on special considerations (purposive sampling) with 21 students in class XI science 2 as a sample of experimental class and 21 students of class XI science 1 as control class. This research instruments were a learning achievement test and questionnaire. Data was analyzed through descriptive statistical analysis, namely test questionnaire data, as well as inferential statistical analysis to test the hypothesis using two-party t-test. Analysis of questionnaire data of students’ learning interests showed that the experimental class was in the agree to category with a percentage of 78.05% while the control class was in the agree category with a percentage of 60.63%. Therefore, it can be concluded that the demonstration method in chemistry learning on colloidal material affects the learning achievement learning interest of students class XI Science of SMA Negeri 1 Kasimbar.

Antioxidant Activity Test of Ethanol and Water Extracts of Celery (Apium graveolens L.) Nurmiati Nurmiati; Siti Nuryanti; Tahril Tahril
Jurnal Akademika Kimia Vol. 9 No. 2 (2020)
Publisher : Universitas Tadulako

This study aimed to determine the antioxidant activity of ethanol and water extracts of celery (Apium graveolens L.). Antioxidant activity test in this study used DPPH (2,2-diphenyl-1-picrylhydrazine) as a source of free radicals and vitamin C as a positive control. The antioxidant activity of celery extracts was analyzed using a UV-VIS spectrophotometer. Celery powder was extracted by firstly the maceration method using different solvents (ethanol and water) and secondly with the decoction method using water solvents. Celery extract was tested for antioxidant activity with various concentrations of 20, 40, 60, and 80 ppm. The results obtained that water extract (maceration) had a very strong antioxidant power with 23.713 ppm of IC50 values, for ethanol extract (maceration) had a strong antioxidant power with 59.492 ppm of IC50 value, water extract (dekok) had also a very strong antioxidant with 77.446 ppm of IC50 value, and vitamin C had a very strong antioxidant power with 15.631 ppm of an IC50 value. Based on the IC50 value obtained, the water extract by the maceration method was very good to be used as a source of natural antioxidants, because it had a very strong antioxidant activity value which was equivalent to vitamin C.

Analysis of Flavonoid Levels in Extract of Gambas Fruit (Luffa acutangula L) Originating from the Village of Posona District Parigi Moutong Aharudin Aharudin; Kasmudin Mustapa; Minarni R. Jura
Jurnal Akademika Kimia Vol. 9 No. 2 (2020)
Publisher : Universitas Tadulako

Gambas fruit (Luffa acutangula L) is a cultivable plant. Gambas fruit can be used as an alternative free radical antidote. The purpose of this study was to determine the level of flavonoids in extract of gambas fruit (Luffa acutangula L) originated from Posona village of Parigi Moutong Regency. This research uses UV-Vis spectrofotometry analysis method. Flavonoids test was done by extracting the sample using 1% HCl solvent in ethanol. The result of the experiment showed that flavonoid level on the fruit of gambas (Luffa acutangula L.) was young gambas 10.60 mg/100g and old gambas 2.62 mg/100g.

Adsorption of Lead(II) Ions using Coconut Fiber’s (Cocos nusifera L.) Activated by Sodium Hydroxide Gatut A. Wardani; Dea D. Pamungkas; Winda T. Wulandari; Fajar Setiawan; Estin Nofiyanti
Jurnal Akademika Kimia Vol. 9 No. 2 (2020)
Publisher : Universitas Tadulako

The use of green coconut fiber waste to adsorb lead(II) ions has been successfully carried out. Coconut fiber was activated first using sodium hydroxide before being used as an adsorbent. The optimum time needed for green coconut fiber to adsorb lead(II) ions was 30 minutes with the percentage of ions adsorbed by 94.34%. The lead(II) adsorption kinetics on green coconut fiber model with R2 value of 0.999 and k value of 38.95 x 10-4 minutes-1. Adsorption isotherm from lead(II) on coconut fiber followed the Langmuir adsorption model with R2 value of 0.984 and adsorption capacity of 0.070 g.mg-1.

Boraxs and Formalin Analysis in the Shumai Treated in Palu City Areeya Milehman; Mery Napitupulu
Jurnal Akademika Kimia Vol. 9 No. 2 (2020)
Publisher : Universitas Tadulako

This study aims to test and prove the presence of borax and formalin contamination in shumai samples sold in Palu City. A qualitative method with curcumin paper test; and quantitatively using the UV-Vis spectrophotometer method on a 550 nm wavelength, so that the borax content can be determined in the sample. From the results of this study as many as 5 shumai samples examined, all samples from 5 samples tested qualitatively positive were found before the quantitative analysis was carried out before the samples were tested qualitatively. Qualitative tests showed that some samples did not contain formaldehyde but positively contained borax so the quantitative test was only conducted to determine borax levels in shumai. The results stated that the lowest level was 0.0213 mg/g and the highest level was 0.0314 mg/g.

Analysis of Student Conception of Atomic Structure at the State SMA in Palu Gavrila Gavrila; Suherman Suherman
Jurnal Akademika Kimia Vol. 9 No. 2 (2020)
Publisher : Universitas Tadulako

This study aimed to analyze student’s knowledge (percent) for who know concept (KC), misconception (MC), and do not know concept (DKC) on the subject of atomic structure at the state SMA in Palu. The sample of this study were students of SMAN Model Terpadu Madani, SMAN 3, and SMAN 9. Data were obtained through tracer tests of students’ conception in the form of multiple-choice consisted of 20 items accompanied by CRI (Certainty of Response Index) which was given to students to determine students' conceptions. Results of the study showed that the percentage of KC, MC, and DKC at SMAN Madani Model Palu were 65.6, 11.3, and 23.2% respectively, while at SMAN 3 Palu were 46.0, 15.1, and 38.9% respectively, and at SMAN 9 Palu were 5.9, 72.6, and 21.5% respectively.

Analysis of Hard Water Coagulation in Water Sources of Kawatuna using Aloe Vera Plant Baby Melyta Pallar; Paulus Hengky Abram; Purnama Ningsih
Jurnal Akademika Kimia Vol. 9 No. 2 (2020)
Publisher : Universitas Tadulako

Aloe vera gel is one of the plants that can be used as a natural coagulant. The chemical content in aloe vera has similarities to the cactus with the presence of mucilage or gel which can be used to purify water. This study aimed to determine the ability of aloe vera gel as a natural coagulant for water purification of Kawatuna water source and to determine the optimum volume of aloe vera gel. The steps of the study were preparing water sample, preparing aloe vera gel, coagulating of water, and analyzing parameters of water qualities i.e hardness, turbidity, color, temperature, pH, and total dissolved solids (TDS). The results showed that aloe vera gel was able to be used as a natural coagulant to purify water with the optimum ratio of 1 mL of aloe vera gel in 500 mL of the water sample. Aloe vera gel reduced turbidity, hardness, and color by 58.33, 15.45, and 50.36%, respectively, with a pH of 4.1, temperatures at 30 oC, and TDS of 77.51%. This study concluded that aloe vera gel able to be used as a coagulant to purify water.

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Daud K. Walanda

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jak.untad@gmail.com

Editorial Address
Program Studi Pendidikan Kimia-FKIP Universitas Tadulako Jl. Soekarno-Hatta Km.9, Palu-Indonesia 94119

Location
Kota palu,

Sulawesi tengah

INDONESIA

Abstract

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Abstract

Home Page

OAI Link

Editorial Team

Contact

Reviewer

Google Scholar

Contact Name Daud K. Walanda

Contact Email walanda@gmail.com

Phone +6281245207927

Journal Mail Official jak.untad@gmail.com

Editorial Address Program Studi Pendidikan Kimia-FKIP Universitas Tadulako Jl. Soekarno-Hatta Km.9, Palu-Indonesia 94119

Location Kota palu, Sulawesi tengah INDONESIA

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Contact Name
Daud K. Walanda

Contact Email
walanda@gmail.com

Phone
+6281245207927

Journal Mail Official
jak.untad@gmail.com

Editorial Address
Program Studi Pendidikan Kimia-FKIP Universitas Tadulako Jl. Soekarno-Hatta Km.9, Palu-Indonesia 94119

Location
Kota palu,

Sulawesi tengah

INDONESIA