Development of Website based Multiple Representation on Buffer Solution Topic in Chemistry Learning

Buffer solution is one of chemistry difficult topics. It contains theory, calculation, and experimentation, so it requires good analysis and understanding of concepts. The
results of interviews with students in Bintan Regency showed that the sub material of determining buffer solution components and analyzing the working principles of buffer
solutions was the most difficult part because it was abstract. Multiple representations on the website media will visualize abstract things from the topic of buffer solution so as to
increase the understanding of concepts from students. The research aims to produce multiple representation website on buffer solution topics and to determine its feasibility,
practicality, and readability. The research method used is research and development (R&D) following the 4D development model by Thiagrajan (define, design, develop, and isseminate). The sample research used 21 students and five chemistry teachers in Bintan Regency to collect user responses related to practicality and readability. The data analysis calculates the average score of the validation and response values and classifies them into the available
categories. The results of the validation show that the average score of material experts is 63.5 (learning, materials, multiple representations, and evaluation aspects), while the average score of media experts is 71.5 (graphic design, software engineering, and media selection criteria aspects), which are classified as very good. The results of practicality and readability responses are 119 (learning, materials, multiple representations, evaluation, graphic
design, software engineering, and media selection criteria) and 70.5 (learning, graphic design, and software engineering), which are very good categories.