Can you identify which period each element belongs to? Test your knowledge of the horizontal rows in the Periodic Table!
Test your knowledge of element periods in the periodic table.
Select your quiz options and click "Start Quiz" to begin.
• Which period does Lithium (Li) belong to? Period 2
• Which period does Argon (Ar) belong to? Period 3
Great job! You know your periodic table well.
Last Updated: Aug 17, 2025
Improved with clearer section comments for each period, notes on the special cases of La/Lu and Ac/Lr, and better organization while keeping the original data format (symbol, name, period, atomic number).