Limits RegistryPUBLIC RECORD
Limits RegistryHelium has the highest first ionization energy of any element, 24.587 eV (2,372 kJ/mol), because its two electrons sit in a compact 1s shell held tightly by the nucleus with no shielding. This is why helium forms no stable neutral chemical compounds under ordinary conditions.
The question, scope, and sources behind this Registry record.
Helium has the highest first ionization energy of any element, 24.587 eV (2,372 kJ/mol), because its two electrons sit in a compact 1s shell held tightly by the nucleus with no shielding. This is why helium forms no stable neutral chemical compounds under ordinary conditions.
The highest energy required to remove one electron from a neutral gaseous atom of any element.
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Current frontiers derived from accepted Claims.
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The frontier as it changed over time.
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1 accepted Claim, with 1 linked evidence records.
Permanent ID limitsregistry.com/limits/LR-HIGHEST-FIRST-IONIZATION-ENERGY
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Limits Registry. LR-HIGHEST-FIRST-IONIZATION-ENERGY. Highest first ionization energy of any element. 2026.