Abstract Several scales of metallicity are briefly analyzed, and a more applicable electronegativity scale is introduced; the concepts of electron affinity energy and electronegativity are analyzed to clarify students' cognition of the most metallic and nonmetallic elements. At the same time, the teaching methods of element periodic law and alkali metals in compulsory 1 of PEP are proposed.
SUN Yu-Han, TIAN Hong-Yu. Caesium and Fluorine:the Most Metallic and Nonmetallic Elements[J]. Chinese Journal of Chemical Education, 2022, 43(5): 102-106.
