The periodic table
This page delivers no verdict; it presents claims and evidence with their sources. No theory in science is absolute. Method
For everyone
Mendeleev arranged the elements by atomic weight and properties and showed that properties recur at regular intervals. He left gaps in the table and predicted the properties of elements not yet discovered. Gallium, scandium and germanium were found in the following years.
For specialists
For "eka-silicon" Mendeleev predicted an atomic weight of about 72 and a density of 5.5 g/cm³; germanium, found by Winkler in 1886, has 72.6 and 5.35. The periodicity was later explained by atomic number (Moseley 1913) and electron shell structure. Lothar Meyer developed a similar table independently. Some of Mendeleev's predictions, such as light elements he proposed for the aether, were not confirmed.
Claims
- The properties of the elements are a periodic function of their atomic weights, allowing unknown elements to be predicted.[1]
Evidence
Supporting
Three predicted elements (gallium 1875, scandium 1879, germanium 1886) were found with properties close to those predicted.[2]
Challenging
Some elements Mendeleev predicted (e.g. "coronium", light elements for the aether) were never found; the role of successful predictions in the table's acceptance is debated.[2]
Connections
Sources
- Article (1869). Sootnoshenie svoistv s atomnym vesom elementov (The relation between the properties and atomic weights of the elements). Zhurnal Russkago Khimicheskago Obshchestva 1, 60–77
- Book (2007). The Periodic Table: Its Story and Its Significance. Oxford University Press
Search the literature
Look for scholarly work on this topic in other indexes:
Cite this page
Athena contributors. (2026). The periodic table. Athena: The tree of human knowledge. Retrieved November 1, 2026, from https://latifkedi.github.io/athena/en/d/mendeleyev/
@misc{athena_mendeleyev,
title = {The periodic table},
author = {{Athena contributors}},
year = {2026},
howpublished = {\url{https://latifkedi.github.io/athena/en/d/mendeleyev/}},
note = {Athena: The tree of human knowledge. Accessed: 2026-11-01}
}Added: September 27, 2026 · Last changed: September 28, 2026 · Page history