First Published Periodic System
Presents the periodic system to the Russian Chemical Society and arranges elements so that chemical properties recur systematically with atomic weight.
Historical biography archive · Updated 2026-11-03
Dmitri Ivanovich Mendeleev Biography and Timeline
Follow Dmitri Ivanovich Mendeleev through 7 dated historical records for Russia.
Dmitri Ivanovich Mendeleev, historical timeline
A chronological timeline drawn from matching World History Database records.
7Distinct records
1 of 1Page
1869–1871Years on this page
1869
Gaps for Undiscovered Elements
Leaves deliberate gaps in the periodic system where the pattern indicates that undiscovered elements should exist.
1871
Eka Aluminium Prediction
Predicts detailed properties for the missing element he calls eka-aluminium, including its approximate atomic weight, density and chemical behaviour.
Eka Boron Prediction
Predicts a missing element related to boron and aluminium, later associated with the discovery of scandium.
Eka Silicon Prediction
Predicts the existence and major chemical properties of a missing element below silicon, later identified as germanium.
Eka-Element Predictions
The achievement marks eka-element predictions as an important Russian scientific milestone.
Predicted Chemical Elements
Publishes detailed predictions for elements missing from the periodic table.
Records, sources and methodology
These dates and descriptions come from the historical_events database. Exact duplicate records have been collapsed. Names are grouped by the country, Name 2 and Name 1 fields; records with missing Name 2 cannot be reliably assigned to an individual biography. Check the underlying sources before formal citation.