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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. 10 No. 3 (2021)" : 10 Documents clear

Profile Secondary Metabolite Compounds and Antioxidant Activities of Stem Bark Jambu Mete (Anacardium occidantale L.) Extract Tarso Rudiana; Dhyneu Dwi Jayanti; Siti Solehah
Jurnal Akademika Kimia Vol. 10 No. 3 (2021)
Publisher : Universitas Tadulako

Oxidative stress is a condition in which the amount of free radicals and antioxidants in the body is not balanced, causing various diseases. One of them is a degenerative disease. Oxidative stress can be reduced by antioxidant compounds. Anacardium occidentale L. is a type of plant from the Anacardiaceae family. This plant is found in many trophic countries included Indonesia, and is believed to ward off degenerative diseases caused by oxidative stress. The purpose of this study was to analyze the activity of A. occidentale stem bark extract against DPPH radical inhibition (1,1-Diphenyl-2-Picrilhidrazil) and the profiling of secondary metabolites in their active fraction. The bark of A. occidentale was extracted by a gradient maceration method. The solvents used were n-hexane (nonpolar), ethyl acetate (semi-polar), and methanol (polar). The macerate was concentrated using a rotary vacuum evaporator, followed by DPPH radical inhibition analysis using a spectrophotometer. The most active extract was analyzed for chemical content by LC-MS/MS. The results showed that the extract of A. occidentale stem bark had antioxidant activity. Methanol extract obtained very strong and best antioxidant activity with an IC50 value of 47.13 ppm compared to ethyl acetate extract and n-hexane extract, which had IC50 values of 163.92 ppm and 501.72 ppm, respectively. Secondary metabolites that are thought to have antioxidant activity in the methanol extract of A. occidentale stem bark were epigallocatechin (EC) and epigallocatechin gallate (EGCG) compounds.

Pre-service Chemistry Teachers’ Mental Model of Colligative Properties for Nonelectrolyte Solutions Kelly Sinaga; Debora S. Sitinjak; Friska J. Purba
Jurnal Akademika Kimia Vol. 10 No. 3 (2021)
Publisher : Universitas Tadulako

Mental models are representations that describe the understanding of the three levels of representation in chemistry, that is macroscopic, sub-microscopic, and symbolic. This study aims to obtain a general description of the mental model of pre-service chemistry teachers in the colligative properties of non-electrolyte solutions. The study was a descriptive research with 22 second-year FIP Chemistry Education students from Pelita Harapan University Tangerang. Data collection was carried out with research instruments in the form of diagnostic tests. The results of the study state that the average percentage level of representation is 67 % macroscopic level, 31% sub-microscopic level, and 72 % symbolic level. The results of this study indicate that students' understanding at the macroscopic and sub-microscopic level of the colligative properties of non-electrolyte solutions was low compared to chemical representations at a symbolic level. Meanwhile, the categories of mental models possessed by pre-service chemistry teachers in the topic of non-electrolyte colligative properties vary for each level of chemical representation. Based on the percentage at each level of representation, the mental model of chemistry teacher candidates with a symbolic model category is higher than the scientific model. The low mental model of the scientific model contributed to the understanding of the pre-service chemistry teachers that the concept of chemistry is not intact scientifically.

Improvement Physics 1 of Chemistry Learning Outcomes Through Project-Based Learning Models (PjBL) Using Quizizz Online Learning Media Leony S. L. Purba; Meida E. Marpaung; Nelius Harefa; Anugrah Purba
Jurnal Akademika Kimia Vol. 10 No. 3 (2021)
Publisher : Universitas Tadulako

Improving cognitive abilities, namely learning outcomes is one of the objectives of learning. Learning outcomes can be improved through the use of creative, innovative learning models in accordance with the current curriculum, the 2013 revised curriculum. This study aims to determine whether there is an increase in Physics Chemistry Learning Outcomes 1 through the Project-based Learning (PjBL) Learning Model using Quizizz online learning media. Based on the results of the normality and homogeneity test, the data is normally distributed with the value of the normality test result of 0.638 (sig 0.05) and homogeneous with the homogeneity test result value of 0.144 (sig 0.05). The results of statistical analysis of research data using the paired t-test hypothesis test results obtained tcount = 17,685 (sig 0.00) and ttable = 0.684 (sig 0.05), it is concluded that there is an increase in learning outcomes in Physics Chemistry 1 through the Project-based Learning (PjBL) learning model using Quizizz online learning media because tcount˃ ttable. A further test is the gain test, to determine the level of improvement in learning outcomes. The results of the analysis using the gain test, the gain value of 42.51%, with the medium category.

Misconceptions Reduction of Science High School Students on Buffer through Remedial Using Conceptual Change Anna Kurnia; Tri Santoso
Jurnal Akademika Kimia Vol. 10 No. 3 (2021)
Publisher : Universitas Tadulako

This study aimed to analyze the results of the reduction of misconceptions among SMA Negeri 5 Palu students on the buffer material using the conceptual change learning strategy. This research is a type of pre-experimental research with a research design that is One group pretest-posttest design. This study contained one experimental group, namely students whose learning outcomes did not reach the minimum completeness criteria (MCC), then given a pre-test to determine the initial state of the experimental group, then given treatment, and given a post-test. Testing student misconceptions data using CRI. The results showed that the average percentage of students, who knew the concept (KC), did not know the concept (DKC), and misconceptions (MC) before the application of conceptual change learning strategies were 38.1%, 45.2%, and 16, respectively. 6% and the percentage of students knowing the concept (TC), not knowing the concept (NKC), and misconception (MC) after the application conceptual change learning strategies respectively 87.4%, 12.6%, and 0%. In conclusion, the average percentage reduction in misconceptions of grade XI IPA SMA Negeri 5 Palu on the buffer through remedial using the conceptual change learning strategy was 16.6%

The Analysis of the Honesty and Responsibility Characters of Chemistry Education Study Program Students on Examinations Suherman Suherman; Sitti Rahmawati; Kasmudin Mustapa; Detris Poba; Nur Azizah
Jurnal Akademika Kimia Vol. 10 No. 3 (2021)
Publisher : Universitas Tadulako

Honesty and responsibility should be a principle held by students. But, there are still problems of dishonesty and irresponsibility of students during exams. This study aimed to analyze the honesty and responsibility character of chemistry students during exams. The research samples were 39 students. Data were collected by observation and interviews technique, by using observation and questionnaires sheets. Data were analyzed by using descriptive statistics. The results showed that the honesty and responsibility of chemistry students were in the sufficient category where the percentage of honesty and responsibility of students based on the observation sheets was 43.6% and 49%, respectively. While the questionnaire responsibility students were 46.2% and 43.6%, respectively.

Conceptual Changes of Students in Thermodynamics in Physical Chemistry Course Through The Implementation of Blended Learning Afadil Afadil; Sitti Rahmawati; Suherman Suherman
Jurnal Akademika Kimia Vol. 10 No. 3 (2021)
Publisher : Universitas Tadulako

This study aims to determine the conceptual changes of students after participating in learning with a blended learning approach on Thermodynamics material. This research is a type of pre-experimental (pre-experimental design) with a One Group Pretest-Postest Design. The blended learning approach is applied using the Problem Based Learning model. The research sample was Class C Odd Semester 2019/2020 students which consisted of 34 students who programmed Physical Chemistry courses. The instrument used is a two-tier multiple choice test which includes concepts in Thermodynamics material which is equipped with a valid CRI. The blended learning approach is one approach that can be used that facilitates student activities in utilizing ICT through the delivery of materials, discussion of task completion, and training in the search for teaching materials on Thermodynamics material. The results showed that misconceptions still occur in every concept of Thermodynamics. The average reduction of misconceptions (MC) is 11.2%, the increase in the number of students to knowing concept (KC) classically is 19.2%, and the decrease in the number of students unknowing concept (UKC) is classically 8.1%. Students' conceptual changes to the material of Thermodynamics are still low. Students are required to understand well the content of the material related to basic concepts, mathematical equations (formulas), and the applicative forms of concepts in everyday life in accordance with the characteristics of the thermodynamic material.

Concentration Effect of Watermelon Skin Extracts (Albedo) as Organic Inhibitors on the Corrosion of Iron Nails in 3% NaCl Medium Solution Nurhikmah Nurhikmah; Minarni R. Jura
Jurnal Akademika Kimia Vol. 10 No. 3 (2021)
Publisher : Universitas Tadulako

This study aimed to determine the concentration effect of skin extract in watermelon on the inhibition of corrosion rates of iron nails in the corrosive medium of NaCl solution and seawater as a comparison. The study began with the first maceration of the skin in watermelon and then followed by evaporation to produce extracts specific gravity 0,097 gram/mL as inhibitors with variations in concentrations of 1, 2, 4, 8, and 16%. The method of determining the corrosion rate used was the weight loss method from the 7-day immersion process. The results showed that the greatest corrosion inhibition efficiency occurred at a concentration of 8% for immersion with 3% NaCl corrosive medium and 4% concentration for immersion in seawater with the efficiency of 11.56% and 22.15%, respectively. Based on the results of the study, it was found that each addition of extract in watermelon can affect the effectiveness of inhibition.

Preliminary Study of Chemistry Knowledge Through Ethnochemistry Approaches to Communities Ade P. Maedja; Purnama Ningsih
Jurnal Akademika Kimia Vol. 10 No. 3 (2021)
Publisher : Universitas Tadulako

This research was a descriptive qualitative study using ethnographic methods. It aimed to determine the understanding and application of chemistry knowledge in the daily lives of Wiapore society, Marawola Barat district, through an ethnochemistry approach. Data obtained was in the form of an initial data inventory. These inventory data were then grouped into several data categories, namely categories related to food, beverage, and agriculture categories. The percentage value of each data was as follows, related to food 55.55%, related to drinks were 22.22%, and connected to agriculture were 22.22%. The results of this study are significant for local governments in taking policies relating to education for children and the Wiapore community

Analysis of Student Misconceptions on the Problem Based Learning (PBL) Model Assisted with Interactive Multimedia on Acid Basic Solutions Fitriani Mandasari; Irwan Said
Jurnal Akademika Kimia Vol. 10 No. 3 (2021)
Publisher : Universitas Tadulako

This study aimed to analyze students' misconceptions on Acid-Base Solution after applying the Problem Based Learning (PBL) model assisted with interactive multimedia in grade XI at SMA 4 Palu. This type of research was a quantitative descriptive study with a total sample of 1 class, namely class XI Science-2, with 33 students. The research instrument used was a reasoned multiple-choice test accompanied by a Certainty of Response Index (CRI) consisting of 15 items. The results obtained the average percentage of students' misconceptions in Problem Based Learning (PBL) assisted with interactive multimedia in Acid-Base Solutions before and after the successive application was 42.9% and 21.8%. Thus the application of the PBL model reduced student misconceptions by 21.1%.

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

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

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Daud K. Walanda

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

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Kota palu,

Sulawesi tengah

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Abstract

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Abstract

Abstract

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