No abstract

The purpose of this study is to find out the quality of the odd chemistry semester exam questions of class X IPA 1 Perbaungan 2017/2018 school year based on qualitative analysis (material, construction, and language), analysis of cognitive level distribution, and quantitative analysis (validity, reliability, power difference, level of difficulty, and effectiveness of deception) using the ANATES V4 program. This study uses a type of quantitative research with descriptive methods. The results of this study are that the content validity in the material is in a very high category, in the construction aspect in the low category and the language aspect in the category is very high. Results based on cognitive domain level distribution are not in accordance with domain level proportions. The results of the study are based on quantitative analysis which is based on validity is 55% valid, and 45% is invalid. Based on reliability is 0.76. Based on the difference in power is good and based on effectiveness the deception is effective.

Infection caused by bacteria is a problem found in various countries, including Indonesia. Different pathogenic bacteria become resistant to some antibiotics. One way to inhibit the activity of these bacteria is to study natural materials that have antibacterial activity. One of the natural ingredients that have these activities is andaliman. It evidenced by the results of the analysis that the diffusion test of Andaliman extract discs uses two types of solvents: n-hexane and ethyl acetate. In the inhibition zone diameter of three types of bacteria, namely: Salmonella typhi, Bacillus subtilis and Staphylococcus aureus and for the antibacterial test several variations of concentration of andaliman extract were used, namely: 12.5 25, 50, and 75%, the best results for n extract -hexane at a level of 50%, namely: 26.7 mm for the best ethyl acetate extract at a concentration of 75%, 21.5 mm, both of the Staphylococcus aureus bacteria. These results indicate that andaliman extract is useful as an antibacterial.

This study aims to determine the feasibility aspect of a problem learning-based website as a learning medium to support online learning on the reaction rate material developed based on BSNP standards. This research consists of three stages, namely the stage of needs analysis based on interviews, observation through goole forms, analysis of learning media and literature study. The development stage begins with compiling a media design, developing, assessing the feasibility of website graphics with the BSNP instrument by one Computer Science lecturer who gets an average score of 3.77 which means very feasible, and assessing the reaction rate material integrated into the website by 3 people Physical Chemistry lecturers and 1 Chemistry teacher get an average content feasibility score of 3.44 which means very feasible, language feasibility of 3.63 means very feasible, and presentation feasibility of 3.66 means very feasible.