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Start with the full category, then apply the exact boundary: IUPAC group 18, atomic numbers 1–30. An element name or chemical symbol is accepted. You only need one qualifying answer. A longer name is not automatically rarer.
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Shortest accepted input at 65+ points
ArArgon · 90 points · 2 characters
Argon (Ar) has atomic number 18 and belongs to group 18, within the 1–30 limit.
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Argon90 points · Shortest accepted spelling: Ar
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3 accepted answers
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- Both the element’s group and the atomic-number limit must fit. A chemical symbol is an accepted spelling, not a way to bypass either restriction.
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Why these answers qualify
Each entry belongs to the bounded set defined by the prompt. The named source supports the underlying facts; our editorial scoring is a separate layer.
Source: IUPAC · Periodic table (4 May 2022) ↗
Reference version: 2026-10-02. See our answer policy for how we handle aliases and omissions.