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Hydrogen MeSH Descriptor Data 2025


MeSH Heading
Hydrogen
Tree Number(s)
D01.268.406
D01.362.340
Unique ID
D006859
RDF Unique Identifier
http://id.nlm.nih.gov/mesh/D006859
Annotation
H or H1; H2 or 2H (superscript) = DEUTERIUM; H2 (subscript) = HYDROGEN; H3 or 3H = TRITIUM; production of H ions = probably PH
Scope Note
The first chemical element in the periodic table with atomic symbol H, and atomic number 1. Protium (atomic weight 1) is by far the most common hydrogen isotope. Hydrogen also exists as the stable isotope DEUTERIUM (atomic weight 2) and the radioactive isotope TRITIUM (atomic weight 3). Hydrogen forms into a diatomic molecule at room temperature and appears as a highly flammable colorless and odorless gas.
Entry Term(s)
Hydrogen-1
Protium
Registry Numbers
7YNJ3PO35Z
Related Numbers
1333-74-0
Date Established
1966/01/01
Date of Entry
1999/01/01
Revision Date
2019/04/05
Hydrogen Preferred
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