Moseley and Periodic Law


Henry Moseley holding a glass-bulb
electron tube

Dmitri Mendeleev made many advancements in the design of the periodic table; however, when he devised his table, there was so much about the atom that was still unknown. As more information about the atom was discovered, this led to changes in the periodic table that Mendeleev could never have anticipated. In this topic, you will learn how a discovery by Henry Moseley changed the periodic table's arrangement. You will also learn about the Periodic Law, which is also known as Mendeleev’s Law.

Essential Questions

  • How is Moseley’s periodic table different when compared to Mendeleev’s?
  • What is the Periodic Law, and how does it apply to the periodic table?