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Jurnal Akademika Kimia
Published by Universitas Tadulako
ISSN : 24775185     EISSN : 23026030     DOI : -
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 201 Documents
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Co-pigmentation of Anthocyanin Jamblang Fruit (Syzygium cumini) with Acetic Acid and Alum Chintia N. Barani; Siti Nuryanti; Paulus H. Abram
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.pp237-246

Abstract

This study aimed to determine the effect of temperature on the stability of anthocyanin jamblang after co-pigmentation with acetic acid and alum. The extraction of Jamblang fruit used the maceration method with n-hexane, ethyl acetate, and ethanol-HCl 0.5% solvents. The total anthocyanin obtained was 70.64 mg/L. Anthocyanin of jamblang fruit was co-pigmented with acetic acid and alum in a concentration of 2.5%; 5%; 7.5%; and 10%, then be heated at various temperatures and heating times. At a temperature of 80 ℃ for 150 minutes, every 30 minutes, absorbance was measured. At a temperature of 60 ℃, the heating was carried out for 225 minutes, and every 45 minutes, absorbance was measured. At a temperature of 40 ℃, the heating was carried out for 300 minutes, and every 60 minutes, absorbance was measured. Absorbance measurements were taken using a UV-VIS spectrophotometer. The results showed that co-pigmentation of anthocyanin occurred proved by shifting λ max from 470 nm (unco-pigmented extract) to 500 nm (co-pigmented extract acetic acid) and 540 nm (co-pigmented extract alum). Acetic acid and alum co-pigments maintained the stability of anthocyanin jamblang at a heating temperature of 60 ℃. It can be seen from decreased absorbance, which is not so significant compared to the decrease at temperatures of 40 and 80 ℃, accompanied by anthocyanin's fading color, which is co-pigmented with acetic acid and alum during the heating process.
Analysis of Students' Skills through Practicum on Reaction Rate Topic Hayatul Islam; Ratman Ratman
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.pp247-253

Abstract

National education emphasizes learning on assessing students' knowledge, attitudes, and skills. The development of skills aspect is not enough only relying on the learning in the classroom, but also necessary doing understanding outside the classroom such as practicum in the laboratory. The implementation of training allows students to practice their skills and help students understand the material taught in the class. This study aimed to describe the quality of students' skills on reaction rate topics through a practicum in grade XI at SMA Negeri 5 Palu. This type of research was a quantitative descriptive study with a one-shot case study design. Sampling was conducted by purposive sampling. The sample was Class XI Science 2 as the experimental class 1 with 23 students and Class XI Science 3 as the experimental class 2 with 25 students. The quality skill of students was measured by instruments in the form of observation sheets as the primary data. The data obtained through the observation sheet showed that the average percentage of all aspects of student skills in experimental class 1 was 74.81%, and in experimental class 2 was 74.05%. It indicates that the ten skills elements have emerged in the learning activities with a good category. This study concludes that the quality skill of grade XI students at SMA Negeri 5 Palu on learning reaction rate topic through practicum is a good category.
The Utilization of Acid as a Color Stabilizer in the Extraction of Anthocyanins from the Lakum (Cayratia trifolia L.) Peel Aryo E. Peluru; Paulus H. Abram
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.pp254-259

Abstract

Anthocyanins are a group of natural dyes (pigments) that give many colors to plants’ leaves, flowers, and fruits. Anthocyanins are generally acidic and more stable under acidic conditions. One of the plants that contain anthocyanin is the lakum (Cayratia trifolia L.) fruit ripe with a blackish-purple color. This study aimed to determine the best type of acid used to extract anthocyanins from the lakum fruit peel. The extraction process was carried out by maceration method using 96% ethanol solvent acidified with three types of acids, HCl 1%, citric acid 3%, and acetic acid 3%, with an average level of anthocyanin obtained of 283.88, 220.70, and 226.55 mg/L, respectively. This study indicated that the best acid used to extract anthocyanin from the lakum fruit peel with the highest total anthocyanin results was by adding HCl 1%.
Copigmentation of Flavonoids of the Gadung Mango Bark (Mangifera Sp) as a Coloring Substance Moh. Sahril; Vanny M. A. Tiwow; Afadil Afadil
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.pp260-268

Abstract

Flavonoids are pigments in the gadung mango bark that produce a yellow color. The research on copigmentation of flavonoids from gadung mango bark (Mangifera sp) as coloring agents was carried out by the maceration method using 96% ethanol. The extract obtained was concentrated using a vacuum rotary evaporator at 40 oC. The study aimed to determine levels of flavonoids and stability of color gadung mango bark on the inner and outer of the result copigmentation as a coloring agent. Measurement of total flavonoid levels at a wavelength of 520 nm and 700 nm using UV-Vis spectrophotometry. The results of this study indicate that the total flavonoids levels in the inner and outer gadung mango bark samples were 0.162 mg/g and 0.359 mg/g, respectively. The color stability of flavonoids of the gadung mango bark inside and outside as the results of copigmentation was stable at the temperature 35 oC and the results obtained in the color stability test of the hero cloth through washing soap water was with a 0 day in 5 hours.
Determination of Iron (Fe), Zinc (Zn) Levels and Organoleptic Tests in Coconut Pulp Flour Muh. F. Khaykal; Sri H. V. Pulukadang
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.pp269-276

Abstract

Coconut pulp is a by-product of coconut milk which contains high protein and good nutrition. This study aimed to determine the iron (Fe) and zinc (Zn) levels in coconut pulp flour using atomic absorption spectrophotometry and determine the characteristics of coconut pulp flour using organoleptic tests. The results showed that iron (Fe) level was 44.075 mg/kg and zinc (Zn) was 24.2 mg /kg. The organoleptic characteristics of the pulp were white and brownish for the dry powder, coconut-scented, a powder-shaped texture, and normal taste. The highest percentage level of hedonic scale for each criterion was 64% preferred for color, 52% preferred for aroma, 48% preferred for texture, and 52% preferred for taste. Based on these results, coconut pulp can be an alternative local food to meet iron and zinc needs for humans. The processing of coconut pulp as food can be used as a substitute flour in making bread, cakes, cookies, and other food preparations.
Application of Cooperative Learning Jigsaw Model to Improve Student's Learning Achievement in Chemistry Learning Sitti Rahmawati; Detris Poba; Magfirah Magfirah; Kusrini Burase
Jurnal Akademika Kimia Vol. 11 No. 1 (2022)
Publisher : Universitas Tadulako

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/j24775185.2022.v11.i1.pp39-45

Abstract

This study aims to improve student achievement in learning chemistry in class X MIA4 at SMA Negeri 1 Palu by applying the Jigsaw Cooperative Learning Model. The Classroom Action Research (CAR) problem can be formulated as follows: Is the Jigsaw Cooperative Learning Model application able to improve student achievement in learning chemistry in class X MIA4 SMAN 1 Palu? CAR is carried out with the following stages to answer the problem: 1. Planning, 2. Implementation. 3. Observation, and 4. Evaluation and Reflection. The study results can be explained as follows several fundamental aspects of learning were successfully improved by applying the Jigsaw Cooperative Learning Model. Such as student activity in collaboration and in completing worksheets independently, actively asking and answering questions, and making students feel happy and enthusiastic. Likewise, the average evaluation of each cycle showed that the % completeness increased. In cycle one, action one was 73.8%, action two 85.5%, and activity three 92.9% increased in cycle two, the average from three actions to 98.0%. It can be concluded that the application of the Jigsaw Cooperative Learning Model can improve student achievement in class X MIA4 SMA Negeri 1.
Synthesis and Characterization of Activated Carbon from Waste Compedak Fruit (Artocarpus Champeden) Activated H3PO4 as Adsorbent of Methylene Blue Catherina Bijang; Matheis F. J. D. P. Tanasale; Dewi Sri; Tahril Tahril; Thamrin Azis
Jurnal Akademika Kimia Vol. 11 No. 1 (2022)
Publisher : Universitas Tadulako

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/j24775185.2022.v11.i1.pp56-63

Abstract

Synthesis of activated carbon from cempedak peel waste is carried out to utilize biomass waste. This study aimed to synthesize and characterize activated carbon from cempedak peel waste. The synthesis was carried out by chemical activation using phosphoric acid with a dry impregnation ratio of 1:4 (g sample:g H3PO4). Samples impregnated for 24 hours were then heated at 250℃—and then calcined at 350℃ and 450℃. The XRD and FTIR characterization results indicated that the activated carbon obtained had an amorphous structure and the activated carbon obtained had hydroxyl, carbonyl, and carboxylic groups. Activated carbon with the highest yield was obtained at a temperature of 350, namely 43%. The results of determining the water content of activated carbon obtained are 8.36% at 350 0C and 7.1% at 450 ℃. The value of water content and ash content of activated carbon from the skin of this cempedak fruit has met the Indonesian National Standard (SNI 06-3730-1995). The best-activated carbon yield was at a calcination temperature of 450, with the percentage of adsorption efficiency on methylene blue of 98.88%.
Characterization of Natural Clay from Gowa Regency, South Sulawesi Province, Indonesia Sumiati Side; Suriati E. Putri
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.pp72-76

Abstract

Clay is one of the essential natural minerals in human life, especially in the industrial sector, which is widely used as a raw material for ceramics fabrication, adsorbents, and photocatalysts. The characteristics of clay significantly affect the quality of the resulting material. This study will study the aspects of natural clay in Gowa Regency, South Sulawesi Province, without the leaching process and with acid leaching. Acid leaching uses 3 M HCl, previously roasted at a temperature of 600 oC. The characterization consisted of metal oxide analysis using XRF, mineral content analysis using XRD, morphological analysis, and compound content using SEM-EDX. The results showed that the primary metal oxide content in natural clay was Fe2O3, Al2O3, and SiO2, the content of Fe2O3 decreased after the raw clay was treated with acid. The main mineral content in the sample is quartz, kaolinite, and hematite. The sample's morphology looks different after being given acid treatment; the acid leaching natural clay sample shows a porous morphology, while the natural clay without acid leaching shows the morphology in the form of lumps. The EDX mapping analysis showed that the number of impurities decreased after being given acid treatment.
Development of Chemistry’s Learning Module Oriented Local Wisdom of Central Sulawesi for High School in Basic Acid Solution Materials Hety E. Panambulo; Ratman Ratman; Nurida Nurida
Jurnal Akademika Kimia Vol. 11 No. 1 (2022)
Publisher : Universitas Tadulako

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/j24775185.2022.v11.i1.pp14-18

Abstract

Development research has been carried out to produce a high school chemistry learning module that oriented Central Sulawesi’s local wisdom in acid-base solutions. This research was conducted using research and development (R&D) methods. The goal of this study was to ascertain the validity and applicability of the developed learning modules. Development of the learning module is expected to be used by teachers as users and for students in their independent learning, increasing the understanding of concepts and getting to know local wisdom in the Central Sulawesi region. The validity of the learning module was determined by a validation test conducted by specialists in the topic, medium, and user. In contrast, the practicality of the learning module was determined by the outcomes of the module's implementation by students. The validation results showed that the average score of the material expert of 2,66 was categorized as “valid,” the average score of the media expert was 3,29 with the category “valid,” and the average score of the user was 3,53 with the category “valid.” The results implementation of learning modules using students' response questionnaires obtained respectively, a percentage of 29% of students responded was “very practical,” 64,4% of students responded war “practical,” 6% of students responded was “impractical,” and 0% of students respond was “very impractical.” Based on these results, it can be concluded that the development module was “valid” and “practical” in using the learning process.
Application of CORE Learning Model with Molymod-Assisted on Hydrocarbon Material to Improve the Students’ Learning Outcomes Gleryl F. Novemly; Mery Napitupulu; Ijirana Ijirana
Jurnal Akademika Kimia Vol. 11 No. 1 (2022)
Publisher : Universitas Tadulako

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/j24775185.2022.v11.i1.pp26-30

Abstract

This study aimed to describe the improvement of learning outcomes by applying the learning model of Connecting, Organizing, Reflecting, Extending (CORE) with molymod-assisted hydrocarbon material of class X students of SMA Labschool UNTAD Palu. This type of research was experimental designs with one group pretest-posttest design. This study used 2 classes, namely class XA as replication class 1 (n = 26) and class XB as replication class 2 (n = 27). The students' learning outcomes were affective, psychomotor, and cognitive aspects. In replication class 1, the value of student learning outcomes was 71.37, while in replication class 2 was 66.00. The data analysis results showed increased student learning outcomes after using the Molymod-assisted CORE learning model in both classes. So it can be concluded that applying the Molymod-assisted CORE learning model on hydrocarbon materials can improve student learning outcomes for class X SMA LABSCHOOL UNTAD Palu.

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