Nelius Harefa
Faculty of Teacher Training and Education, Universitas Kristen Indonesia, Jakarta 13630, Indonesia

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Effectiveness of use of online games kahoot! chemical to improve student learning motivation Leony Sanga Lamsari Purba; Elferida Sormin; Nelius Harefa; Sumiyati Sumiyati
Jurnal Pendidikan Kimia (JPKim) Vol 11, No 2 (2019): August
Publisher : Pascasarjana Universitas Negeri Medan

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (286.415 KB) | DOI: 10.24114/jpkim.v11i2.14463

Abstract

Qualitative descriptive study quasi-experimental method is intended to determine the effectiveness of using online games Kahoot! to increase student motivation to learn chemistry. The population in this study were all students of class X private secondary schools (SMAs) Pusaka 1 Jakarta. The sample was selected by random sampling technique, the entire class X MIA 1 with the number of 40 students. The results showed the use of online games Kahoot! effective to increase student motivation to learn chemistry. Increased motivation to learn by using the test gain with the gain of 0.73 with the interpretation of the increase motivation to learn the high category. All the indicators of motivation to learn, which has the intention to succeed in learning, to feel the need to be learned, have ideals, appreciate the lessons and study give a percentage increase motivation to learn different. The most significant increase occurred in the indicator have a desire to succeed in learning, with high gain values, namely 0.82. The lowest increase occurred in the indicator value learning, the value of the gain medium, which is 0.70. Thus, the use of online games Kahoot! help improve students' motivation to learn chemistry when applied to learning. Kahoot! use of online games! help improve students' motivation to learn chemistry when applied to learning. Kahoot! use of online games! help improve students' motivation to learn chemistry when applied to learning.Keywords:Chemical; industry 4.0; kahoot!; learning; media; motivation
The differences of achievement of the national olympiad in chemistry at the public and private senior high school by utilizing quizizz media Leony Sanga Lamsari Purba; Nelius Harefa; Sali Afridika; Dera Savera
Jurnal Pendidikan Kimia (JPKim) Vol 13, No 1 (2021): April
Publisher : Pascasarjana Universitas Negeri Medan

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (281.436 KB) | DOI: 10.24114/jpkim.v13i1.24146

Abstract

This research is a quantitative study which aims to determine the results differences of the 2nd National Chemistry Olympiad at the public and private senior high school using quizizz media. All participants of the population were sampled in the determination, the sampling technique used was saturated samples. The results of the prerequisite test on the data from this study showed that the data were normally and homogeneous. For normality and homogeneity tests, obtained sig > 0.05. Data analysis using SPSS 24, carried out One Way Anova test, obtained sig.0.01 with a significance level of 5%, these results indicate that there are differences in the results of the 2nd National Chemistry Olympiad (OKN) level is low, the public high school participants results with an average score of 59.48 and private high schools with an average score of 41.95 by utilizing Quizizz media.Keywords: Chemistry, Olympics, Learning, Quizizz
The difference of students’ learning outcomes with project based learning using handout and sway Microsoft 365 Nelius Harefa; Novia Fransisca Dewi Silalahi; Elferida Sormin; Leony Sanga Lamsari Purba; Sumiyati Sumiyati
Jurnal Pendidikan Kimia (JPKim) Vol 11, No 2 (2019): August
Publisher : Pascasarjana Universitas Negeri Medan

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (190.077 KB) | DOI: 10.24114/jpkim.v11i2.14459

Abstract

This study aimed to determine the difference of students’ learning outcomes with project based learning using handout and sway Microsoft 365. The sample was selected using purposive sampling into experimental group I and experimental group II with 64 students. The experimental group I used the project based learning using sway Microsoft 365, while the experimental group II used the project based learning using handout. The difference test between experimental group I and experimental group II student tcount (5.411) > ttable (2.425) at significance α = 0.05, it concluded that there was the difference of students’ learning outcomes used project based learning using handout and sway Microsoft 365.Keywords:Handout; learning outcomes; project based learning; sway Microsoft 365
The development of chemistry practicum e-module based on simple-practice Nelius Harefa; Leony Sanga Lamsari Purba
Jurnal Pendidikan Kimia (JPKim) Vol 11, No 3 (2019): December
Publisher : Pascasarjana Universitas Negeri Medan

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (188.164 KB) | DOI: 10.24114/jpkim.v11i3.15739

Abstract

Practicum is an important element in chemistry. In chemistry learning with practical methods students are given the opportunity to be creative, find, or prove a phenomenon that he experienced and the concepts his learned. Therefore, it is important to develop the learning method using practicum to accommodate the progress and needs of the times so that learning is close to students so that learning becomes meaningful. In this research, the development of digital integrated chemistry practicum modules based on simple practice is carried out. The research sample consisted of 248 students and 26 chemistry teachers, and was validated by 3 expert judges. In the initial stage, the module developed is validated by expert judges. The validation results show that the module is categorized as valid in terms of content eligibility, language feasibility, and presentment eligibility with an average score of 3.81 (scale 4). In the final stage, a module testing is conducted for chemistry students and teachers in the form of collecting responses. Chemistry teacher response results indicate that the module is feasible to be used as a source of student learning on chemistry practicum class XI high school even semester with an average score of 3.78 (scale 4). The results of the students' responses showed that the module was appropriate for them to use as a source of learning on chemistry practicum with an average score of 3.79 (scale 4). The results of student responses on the presentment eligibility aspect showed the highest value of 3.98 (scale 4), the module developed was presented digitally integrated which can be accessed online.Keywords: Chemistry; e-module; practicum; simple-practice
Improvement of students learning outcomes and motivation with chemical practicum e-module Nelius Harefa; Novia Fransisca Dewi Silalahi
Jurnal Pendidikan Kimia (JPKim) Vol 12, No 1 (2020): April
Publisher : Pascasarjana Universitas Negeri Medan

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (379.976 KB) | DOI: 10.24114/jpkim.v12i1.17708

Abstract

The use of modules has an effect on students’ motivation and students’ learning outcomes. Based on the analysis of learning outcomes data using paired sample t-test SPSS 21 shows that tcount (4.872)> ttable (2.354) at significance α = 0.05, which means that there are differences in students’ learning outcomes taught using chemistry practicum e-modules and practicum modules conventional. Students’ learning outcomes by utilizing the chemistry practicum e-modules are higher than students’ learning outcomes by utilizing conventional practicum modules. 93.24% of students have very strong motivation to study in the laboratory by utilizing the chemistry practicum e-module while by utilizing conventional practicum modules by 72.98%. Meanwhile, the Pearson Correlation test is 0.613 at significance α = 0.05, which means that there is a strong relationship between learning motivation and student learning outcomes. Keywords: Chemistry; e-module; learning outcomes; motivation; practicum
Identification of metal content in food using gravimetric and iodometric methods: The case on children's food Nelius Harefa; Saronom Silaban
Jurnal Pendidikan Kimia (JPKim) Vol 12, No 2 (2020): August
Publisher : Pascasarjana Universitas Negeri Medan

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (396.277 KB) | DOI: 10.24114/jpkim.v12i2.19395

Abstract

The metal content is one indicator of the eligibility of food consumption, including food for children. In this research, identification of Lead (Pb), Mercury (Hg), Cadmium (Cd), and Arsenic (As) metals on pentol, bakso, cilok, cireng, and cimin samples by gravimetric and iodometric methods. The identification of metals by the gravimetric method shows that the metal content in all samples is below the threshold, where the highest metal content is the lead metal in the cimin sample of 0.0439 mg/kg. The identification of metals by the iodimetry method showed that the metal content in all samples was below the threshold, where the highest metal content is the lead metal in the cimin sample of 0.0436 mg/kg. Thus, all samples are categorized as safe for consumption.  Keywords: Gravimetric, Iodometric, Metals content
Analysis of BOD and COD levels for home industry wastewater: A case study in a sewage streams Nelius Harefa; Arifman Gulo; Saronom Silaban
Jurnal Pendidikan Kimia (JPKim) Vol 13, No 1 (2021): April
Publisher : Pascasarjana Universitas Negeri Medan

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (383.149 KB) | DOI: 10.24114/jpkim.v13i1.24142

Abstract

Environmental pollution caused by waste is pollution that very dangerous for living things. In particular, water pollution, waste that is disposed of through waterways will disrupt the water ecosystem which will have an impact on human life. On the other hand, the development of entrepreneurship such as home industry has a positive impact on society, especially in terms of the economy. Therefore, water pollution indicators are needed that can be used as guidelines in treating wastes such as BOD and COD. In this study, analyzed the levels of BOD and COD from home industry wastewater in the Cawang area. The home industry includes laundry, cracker business, restaurants, printing houses, photocopying, and snack businesses. Based on the results of data analysis, the highest BOD level was 45.827 in samples taken at night. And, the highest COD levels were 95.923 in samples taken at night. These data indicate that the levels of BOD and COD in the water in the home industry waste disposal sites are below the standard threshold for wastewater quality. The levels of BOD and COD are in the safe category for aquatic biota.Keywords: BOD levels, COD levels, Waste, Water pollution
Students perception and interest on chemistry: Learning evaluation integrated quizziz media Nelius Harefa; Marudut Sinaga; Saronom Silaban
Jurnal Pendidikan Kimia (JPKim) Vol 12, No 3 (2020): December
Publisher : Pascasarjana Universitas Negeri Medan

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (346.995 KB) | DOI: 10.24114/jpkim.v12i3.21163

Abstract

Interest in learning is a passion or a great desire for something that is closely related to personality, motivation, expression and self-concept, identification, heredity, and external factors. Interest in learning affects the cognitive, affective, and psychomotor aspects of students. In this study, analyzed and interpreted student interest in learning through media-based learning Quizizz and students' perceptions of the media. Based on the analysis and interpretation of the data, indicators of student interest in the media Quizizz increased by 0.818 in the high category, indicators of student attention increased by 0.555 in the medium category, indicators of feelings of pleasure increased by 0.684 in the medium category, and indicators of student involvement increased by 0.599 in the medium category. Also, 76.32% of students thought that Quizizz media were very interesting, 50% thought that Quizizz media were easily applied, 86.84% thought that Quizizz media accommodate students to compete fairly, and 44.74% thought that Quizizz media were practically applied. Thus, students have a good perception of the Quizziz media accompanied by increased interest in learning.Keywords: Learning evaluation, Students’ perceptions, Students’ interest, Quizziz media