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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 137 Documents

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Citric Acid Extraction in Citrus hystrix Peels as an Alternative Material for Reducing Water Hardness Ni Nyoman Suciani; Irwan Said; Anang Wahid M. Diah
Jurnal Akademika Kimia Vol. 10 No. 1 (2021)
Publisher : Universitas Tadulako

Water hardness will have a destructive impact if consumed in a long time. Hard water contains high calcium contents, including inorganic calcium. The accumulation of calcium in the body at a specific time causing kidney stones, and some will settle in the blood that causing calcification which can be fatal to health. An alternative is needed to reduce the level of water hardness. This study aimed to determine the effect of using citric acid on citrus hystrix peels on water hardness. Citric acid was obtained through the maceration extraction method from citrus hystrix. The citric acid extract was made into several concentrations of 50, 100, and 150 ppm then added to hard water. Determination of decreased total water hardness after adding citric acid used method complexometry titration. The results of the analysis show that citric acid is able to reduce water hardness of the sample water from Palu city area.

Influence of the Guided Inquiry Learning Model Assisted by a Two-stay Two Stray towards Chemistry Learning Outcomes of High School Students Dahlia Sofiyatun; Minarni R. Jura; Sri M. Sabang
Jurnal Akademika Kimia Vol. 10 No. 4 (2021)
Publisher : Universitas Tadulako

This study aimed to determine the influence of the guided inquiry learning model assisted by two stay two stray toward learning outcomes of students on chemistry at SMA 7 Palu. The type of study was Pre-experimental with a one-shot case study design. The sample was prepared using the purposive sampling technique with a sample consisting of Class XI Science 4 as the experimental class 1, and Class XI Science 2 as the experimental class 2. Both classes consisted of 28 students. The research instruments were the learning outcomes tests, student worksheets, and observation sheets that have been validated theoretically and empirically. Data of learning outcomes was analyzed using inferential statistical analysis with a prerequisite test: normality, homogeneity, and t-test hypothesis test (right side). The results showed that the average learning outcomes for experimental class 1 was 62.32, and for experimental class 2 was 50.29, with standard deviations of 12.58 and 12.05, respectively. Hypothesis test obtained tcount>ttable or 4.04 > 1.67, so H1 is accepted. The average learning outcomes of students in the experimental class 1 with guided inquiry learning model assisted by two stay two stray is higher than in the experimental class 2 with a guided inquiry learning model. Guided inquiry learning model assisted by two stay two stray influences learning outcomes of students at SMA 7 Palu.

Adsorption Capacity of Activated Charcoal Made of Rice Husk on Cd(II) Metal Ions Eka Widyasari; Supriadi Supriadi; Irwan Said
Jurnal Akademika Kimia Vol. 10 No. 4 (2021)
Publisher : Universitas Tadulako

Rice husk is one of the by-products of the rice milling process that can be used as activated charcoal to adsorb metal ions. This study aimed to determine the optimum pH and adsorption capacity of Cd(II) ions by activated charcoal made of rice husk using the Atomic Absorption Spectrophotometry (AAS) method. Determination of the optimum pH adsorption of activated charcoal was carried out by varying the pH of 2, 3, 4, 5, 6, 7, and 8. Based on the analysis results of the optimum pH for metal adsorption, pH 7 with percent absorbed metal 99.94%, while adsorption of Cd(II) ions using activated charcoal was carried out with several variations of concentration to study adsorption isotherm. The adsorption isotherm model of activated charcoal adsorption followed the Langmuir isotherm model. The results of this analysis obtained that the maximum adsorption capacity (qmax) of Cd(II) ions were 2.068 mg Cd/g.

The Utilization of Aleorites Moluccana Active Charcoal as Absorbent of Lead Metal in Used Oil Wayan N. Sugiani; Vanny M. A. Tiwow; Minarni R. Jura
Jurnal Akademika Kimia Vol. 10 No. 2 (2021)
Publisher : Universitas Tadulako

Candlenut (Aleurites moluccana) shell is a waste produced from the processing of the plants having a fairly hard texture. This study aimed to determine the optimum weight and contact time for the candlenut activated carbon which can absorb lead metal in used oil. Analysis of lead levels was carried out using atomic absorption spectropometry (AAS). Determination of the optimum weight and contact time of activated charcoal was carried out on various weight of 3 g, 6 g, and 9 g, as well as various times of 1, 2, and 3 hours, respectively. The results show that the optimum weight and contact time of activated charcoal are 9 g for 3 h with the percentage of lead concentration absorbed of 90.716%.

Application of Inquiry Learning Model with Lesson Study (LS) Pattern on Student Learning Outcomes in Colloid System Material Nur H. Wahyuni; Suherman Suherman; Tahril Tahril
Jurnal Akademika Kimia Vol. 10 No. 2 (2021)
Publisher : Universitas Tadulako

This study aimed to know the effect of applying the inquiry learning model with lesson study (LS) pattern on student learning outcomes in colloid system material in class XI SMA Negeri 1 Sigi. This type of research was a quasi-experiment with an equivalent post-test design. Samples were determined by the purposive sampling method. The sample used in this study was students of class XI MIA 3 as an experimental class with 24 students and XI MIA 4 students as a control class with 20 students. The processing of student learning outcomes data used a non-parametric analysis of the Mann-Whitney U-Test test. The results showed that the mean value of the experimental class was higher than the control class, which was 23.98>15.82. Results of statistical analysis sig. 2-tailed was (0.019) <0.05 and Zcalculation (-2.336) < Ztable (-1.96), based on decision-making criteria, it stated if the value of -Zcalculation<Ztable then H0 is rejected. Therefore, it can be concluded that there is the effect of applying the inquiry learning model with lesson study (LS) pattern on student learning outcomes in colloid system material in class XI SMA Negeri 1 Sigi.

Analysis of Lycopene Content and Antioxidant Activity Test of Katokkon Chili Extract (Capsicum chinense Jacq) Febryna V. Maddo; Siti Aminah; Afadil Afadil
Jurnal Akademika Kimia Vol. 10 No. 4 (2021)
Publisher : Universitas Tadulako

This study aimed to determine lycopene contents and the antioxidant activity of katokkon chili extract. The extraction process of katokkon chili used the maceration method with the mixture of n-hexane : acetone : ethanol (2:1:1). The concentrated extract of katokkon chili was obtained through the evaporator process at a temperature of 40 ˚C. The analysis process used a UV-Vis spectrophotometer in which the absorbance reading was at λ = 472 nm. The average content of lycopene in katokkon chili extract was 1.457 mg/100g. Testing the antioxidant activity of katokkon chili extract used the DPPH (2,2-diphenyl-1-picrylhydrazyl) method with positive control the vitamin C. The absorbance readings for the antioxidant activity test were at λ = 517 nm. The test results showed that the antioxidant power of katokkon and vitamin C extracts in reducing DPPH free radicals had a similar result which was equally strong. The IC50 value for chili katokkon extract was 13.84 mg/L, and the IC50 value for vitamin C was 5.78 mg/L, so it can be concluded that chili katokkon can be an alternative source of natural antioxidants to replace vitamin C.

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

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.

Implementation of Guided Inquiry Learning Model on Colloid Systems to Improve Critical Thinking Ability of Students Nurul R. Arini; Sri M. Sabang; Anang W. M. Diah
Jurnal Akademika Kimia Vol. 10 No. 2 (2021)
Publisher : Universitas Tadulako

Critical thinking is the ability to solve problems through an investigation so as to produce conclusions or rational decisions. This study aimed to obtain an improvement of critical thinking skills of students in Grade XI at SMAN 3 Palu after the implementation of the guided inquiry learning model on Colloid Systems. This study was a pre-experiment with one group pretest-posttest design. The sample was run by simple random sampling with the sample of Class XI Science 1 as the replication class 1 (n = 36) and Class XI Science 3 as the replication class 2 (n = 35). Data on students' critical thinking was taken using tests that were given before and after learning. An improvement in students' critical thinking skills in replication class 1 and replication class 2 was by 50%. Data of students' critical thinking skills were tested using non-parametric statistical analysis, namely the Mann-Whitney test. The test results obtained the Zh value -0.076, so -1.96 ≤ -0.076 ≤ +1.96. This result is in the reception area of Ho, and H1 is rejected. It means that the average score of critical thinking ability of students in the replication class 1 is the same as in replication class 2. This study concluded that the implementation of the guided inquiry learning model on Colloid Systems improves the critical thinking skills of students in Grade XI at SMAN 3 Palu.

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.

Development of Hollow Fiber Liquid Phase Microextraction Method for Determination of Diazinon Residues in Vegetable Samples Eviomitta R. Amanda; Yanuardi Raharjo; Usreg S. Handajani
Jurnal Akademika Kimia Vol. 11 No. 1 (2022)
Publisher : Universitas Tadulako

An extraction method based on a combination of hollow fiber liquid-phase microextraction with high-performance liquid chromatography diode array detector (HF-LPME HPLC-DAD) has been developed and demonstrated to analyze pesticide residues in vegetables. This study aims to determine the optimum extraction conditions and validation performance of this method. Diazinon pesticide was selected as the target model analyte. HF-LPME is performed by stacking microliter organic solvent droplets through an HPLC syringe coated with polypropylene hollow fiber by directly dipping it into the sample solution and stirring it during the extraction process. Finally, the organic solvent was put into an HPLC syringe at the end of the extraction. Then, it was injected into the HPLC-DAD at the wavelength of 247 nm. Several important extraction parameters have been optimized. The optimization results showed the type of organic solvent of n-hexane, the length of the hollow fiber of 1.5 cm, the volume of the sample solution of 20 mL, and the stirring speed of 600 rpm. The validation performance obtained a limit of detection (LoD) of 0.10 mgL-1, limit of quantification (LoQ) of 0.33 mgL-1, percent recoveries of 99.88%, a coefficient of variation of 3% (n=15), and the enrichment factor of 19,982 times. Under optimal conditions, the developed method was applied to extract diazinon in vegetable matrix samples using the spiking method. Mustard green was selected as a model matrix sample. From the research, the percentage recoveries of diazinon obtained in the mustard green matrix sample are 98.80% - 100.41%.

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Daud K. Walanda

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jak.untad@gmail.com

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

Location
Kota palu,

Sulawesi tengah

INDONESIA

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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