Zusammenfassung der Ressource
C3-History of periodic table
- Newlands 1864
- Every 8th element had similar properties - Newlands' Octaves.
- The pattern broke down on the 3rd row. He left no gaps for undiscovered
elements.
- Groups contained elements that didnt' have similar properties and he mixed up metals and
non-metals
- Dmitri Mendeleev-1869
- Arranged elements in order of atomic mass like Newlands
- Left gaps in order to keep elements with similar properties in same vertical columns
- Newly discovered elements fit into his table perfectly.