THE DEVELOPMENT OF VIRTUAL LABORATORY TO IMPROVE STUDENT CRITICAL THINKING SKILLS ON THE TEACHING OF GAS CHROMATOGRAPHY

The industrial revolution 4.0 is increasingly intense and sophisticated technology affects learning activities. Learning activities that are usually do face-to-face now can be do online. Virtual laboratory is one of the facilities developed to fulfill learning activities. The purpose of this study is to develop gas chromatography learning media, validate learning media, implement learning media developed with the hope of increasing students' critical thinking skills and getting learning outcomes, seeing student responses to the developed learning media, and to see the effectiveness of the developed learning media. This study uses the R & D method with analysis, design, development, and implementation techniques. Based on the research, the data obtained from the validation of learning media as a whole is 96.75%, including in the good category and suitable for use. The students' critical thinking achievement was obtained with a score of M ± SD 82.51 ± 2.87 with a good category. Improved learning outcomes obtained N-gain 0.57 and included in the category of moderate improvement. The effectiveness of the media gets an overall percentage of 76.43% and is in the good category, and is shown by the learning implementation sheet with an overall percentage of 78.52% and is included in the good category. Thus the virtual laboratory-based learning media developed in this study is categorized as good and suitable for use in learning and can improve students' critical thinking skills.