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How Many Periods are in the Periodic Table?

How many periods are in the periodic table? Find the answer to this question and access a vast question bank that is customised for learners.

Answer: A chemical element’s atomic number is its position in the periodic system, which places the atoms in ascending order of the number of protons in their nuclei.

The periodic table has seven periods, with the first containing two elements.

  • Hydrogen and helium.
  • The second and third periods contain eight elements ranging from lithium to Argon.
  • The fifth period contains 18 elements ranging from potassium to xenon.
  • The sixth and the seventh periods contain 32 elements ranging from caesium to oganesson. 
  • Furthermore, 14 elements from each row are presented on separate lines known as lanthanides and actinides.