Bahrizal Bahrizal
Jurusan Kimia FMIPA Universitas Negeri Padang

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Penggunaan Teknik Talking Chips pada Model Kooperatif Hasil Belajar dalam Pembelajaran Tata Nama Senyawa dan Persamaan Reaksi Kimia di SMAN 2 Pariaman Bayharti, Bayharti; Bahrizal, Bahrizal; Fitriani, Rahmi
Jambura Journal of Educational Chemistry Vol 12, No 1 (2017): Februari
Publisher : Jambura Journal of Educational Chemistry

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Abstract

The goal of this study is to know the effect of using techniques talking chips on the cooperative learning in study of nomenclature of compounds and the chemical reaction at SMAN 2 Pariaman. The model used is a cooperative learning with talking chips technique that can improve students' learning activity. This research is a quasi-experimental research which design of Randomized Control Group Posttest Only Design. The population of this study were all students of class X SMAN 2 Pariaman. The sampling technique used was cluster sampling X.1 class is experimental and X.2 class is the control class. The data collection was done by administering tests at the end of the study. This research found that the average value of student score at experimental class is 76.33 and those of control class is 69.4. Both of these data are found normal and homogen. Data analysis used was t-test on a real level of 0.05 that obtained tcount = 2.605 and ttabel1.67. This means tcount> ttabel, and the research hypothesis is accepted. It can be concluded that there is a significant increase from the results of studying chemistry by using the technique of talking chips on the cooperative model in study of nomenclature of compounds and chemical equations.
PERBANDINGAN HASIL BELAJAR MENGGUNAKAN MODEL PEMBELAJARAN KOOPERATIF TIPE STAD DAN CRH PADA MATERI HIDROLISIS GARAM Amida, Nadia; Andromeda, Andromeda; Bahrizal, Bahrizal
Alotrop Vol 2, No 2 (2018)
Publisher : FKIP University of Bengkulu

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Abstract

Lesson about  hydrolysis  requires students to understand the concepts hydrolyzed from  type of salt which is then applied in the calculation. In  learning process, students direct involvement is necessary, so that it is used a method that can increase the activity of students. Student Teams Achievement Division (STAD) cooperative learning and Course Review Horey (CRH) expected to create learning that has caharacterized as student centered.  This research aims to reveal students' learning outcomes using STAD cooperative learning and CRH on the hydrolisis material in class XI SMAN 8 Padang. This type of research is experimental research using a randomized study design Control Group Posttest-Only Design is expanded. The study population was a class XI IPA SMAN 8 Padang. Giving  a test at the end of the study as many as 25 pieces of matter objectively. Results of tests of normality and homogeneity of the two classes that both classes of samples obtained samples were normally distributed and had homogeneous variance. After being tested on a real level t = 0.05 with degrees of freedom (df) of 59 obtained t of 2.53 while t table of 1.67. From the research shows that the learning outcomes of students with STAD cooperative learning model is significantly higher than the results of student learning with cooperative learning model CRH hydrolysis of salts in the material in class XI of SMAN 8 Padang.
PREPARASI DYE SENSITIZED SOLAR CEL MENGGUNAKAN EKSTRAK ANTOSIANIN KULIT BUAH MANGGIS (Garcinia Mangostana L) Maulina, Anna; Hardeli, Hardeli; Bahrizal, Bahrizal
Sainstek : Jurnal Sains dan Teknologi Vol 6, No 2 (2014)
Publisher : IAIN Batusangkar

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (599.364 KB) | DOI: 10.31958/js.v6i2.115

Abstract

This study aims to determine the effect of the concentration of semi-solid electrolyte/polymer gel and determine the effect of the dye absorption technique on TiO2 paste the resulting DSSC efficiency. The results obtained by XRD characterization of TiO2 crystal phase is anatase and rutile TiO2 with a crystal size of 30.27 nm. Based of testing the light absorption of dye extract of purple sweet potato is known that the spectrum of the dye can absorb light at 533 nm wavelength maximum. The result of the conversion of sunlight into electrical energy obtained the highest value is at the highest PEG concentration at 0.1 M is 0,38% for TiO2 paste is mixed directly with the dye and 0,23% for TiO2 paste soaking in the dye for 24 hours using an electrolyte semi-solid/gel polymer with an area of 1 cm2.Key words: Anthocyanin, DSSC, semi-solid electrolyte, FTIR, UV-Vis, XRD