Talk:Periodic table

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The content of Placement of lanthanides and actinides in the periodic table was merged into Periodic table. The former page's history now serves to provide attribution for that content in the latter page, and it must not be deleted as long as the latter page exists. For the discussion at that location, see its talk page.

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"inner electrons responsible for chemical properties" ?

"Bohr then attempted to understand periodicity through electron configurations, surmising in 1913 that the inner electrons should be responsible for the chemical properties of the element."

Really, *inner* electrons? That is unintuitive. If the statement is correct it needs some extra words to make that clear - perhaps just put (sic) after "inner". ~2025-33904-40 (talk) 03:15, 6 February 2026 (UTC)[reply]

The cited article, Kragh 2012, doesn't support that statement: According to Bohr, the chemical similarity between elements in the same group was a result of the atoms having the same number of electrons in the outermost ring (and not, as J. J. Thomson had earlier suggested, in the inner rings.) Jähmefyysikko (talk) 03:58, 6 February 2026 (UTC)[reply]

@Jähmefyysikko That seems sufficient justification to change "inner electrons" to "outer electrons". Please make that change - the article is locked for me. ~2025-33904-40 (talk) 06:52, 6 February 2026 (UTC)[reply]