Kristiana E, Sidauruk S, Meiliawati R. Difficulties of Class X High School Students in Palangka Raya City in Understanding the Concept of Lewis Structures Using Two-Tier Multiple Choice Instruments. JIKT [Internet]. 2020Jun.30 [cited 2025Aug.26];11(1):200-8. Available from: https://www.chem-upr.education/ojs/index.php/JIKT/article/view/87