The evolution of fundamental concepts in organic chemistry: Hydrocarbons in Iranian secondary school chemistry textbooks and their information content and importance based on shannon entropy

Background and Objective: This study examines the changes in the basic concepts of the chemistry of different branches of hydrocarbons (alkanes, alkenes, alkynes, and aromatics) in high school chemistry textbooks from ۱۹۷۱ to ۲۰۲۱. Methods: This applied study, following a historical method, uses content analysis. Shannon entropy is applied to data processing and validation. Textbooks from ۱۹۷۵, ۱۹۸۵, ۱۹۹۹, ۲۰۰۹, and ۲۰۱۹ were samples. Findings: The concepts were extracted and counted, and their frequencies were calculated. The results show that in ۱۹۷۵ aromatics had the highest frequency (۳۲.۰۴%) and alkenes the lowest (۲۰.۲۴%). In ۱۹۸۵, aromatics and alkenes were highest (۲۸.۰۷%) and alkynes lowest (۲۱.۰۵%). In ۱۹۹۹, alkenes were highest (۲۹.۴۱%) and alkynes lowest (۱۹.۶۱%). In ۲۰۱۹, alkanes were highest (۵۰.۰۰%) and aromatics lowest (۹.۰۹%). In ۲۰۱۹, alkenes were the highest (۵۰.۰۰%) and alkynes and aromatics lowest (۹.۰۹%). Conclusion: Comparisons across branches show alkanes peaked in ۱۹۹۹ (۵۰.۰۰%) and were lowest in ۱۹۷۵ (۲۲.۸۱%). Alkenes peaked in ۲۰۱۹ (۵۰.۰۰%) and were lowest in ۱۹۸۵ (۲۰.۲۴%). Alkynes peaked in ۱۹۷۵ (۲۲.۶۲%) and were lowest in ۲۰۱۹ (۹.۰۹%). Aromatics peaked in ۱۹۷۵ (۳۲.۵۴%) and were lowest in ۲۰۱۹ (۹.۰۹%). Shannon entropy analysis shows alkenes had the highest information content and also importance, and aromatics had the lowest. Across years, the highest information content was in ۱۹۸۵ and the lowest in ۲۰۱۹. The highest importance was in ۲۰۱۹ and the lowest in ۱۹۷۵.

کلیدواژه ها:

Key ideas ، Fundamental concepts ، Experimental Sciences ، chemistry ، Shannon Entropy ، importance