Glossary · term

Periodic table

Chemistry

Domain
Chemistry

Definition

The elements ordered by atomic number so that each column shares an outer-electron structure, and therefore its chemistry. Mendeleev left gaps in 1869 and the missing elements arrived where he had put them.

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From the Glossary database in Notion, last edited 2026-08-17. This page is the row, rendered by the build; nothing on it is written by hand.