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Substance Name: Hydrogen
RN: 1333-74-0
UNII: 7YNJ3PO35Z

Note

  • The first chemical element in the periodic table. It has the atomic symbol H, atomic number 1, and atomic weight [1.00784; 1.00811]. It exists, under normal conditions, as a colorless, odorless, tasteless, diatomic gas. Hydrogen ions are PROTONS. Besides the common H1 isotope, hydrogen exists as the stable isotope DEUTERIUM and the unstable, radioactive isotope TRITIUM.

Molecular Formula

  • H2

Molecular Weight

  • 2.0159
 

Classification Code

  • Simple Asphyxiant

Names and Synonyms

Name of Substance

  • Hydrogen

MeSH Heading

  • Hydrogen

Synonyms

  • EINECS 215-605-7
  • H
  • HSDB 5026
  • Hydrogen
  • Hydrogen atoms
  • Molecular hydrogen
  • Protium
  • UNII-7YNJ3PO35Z

Systematic Name

  • Hydrogen

Superlist Names

  • Hydrogen
  • Hydrogen, compressed
  • Hydrogen, compressed [UN1049] [Flammable gas]
  • Hydrogen, refrigerated liquid (cryogenic liquid)
  • Hydrogen, refrigerated liquid (cryogenic liquid) [UN1966] [Flammable gas]
  • UN1049
  • UN1966

Registry Numbers

CAS Registry Number

  • 1333-74-0

FDA UNII

  • 7YNJ3PO35Z

Other Registry Number

  • 725200-57-7

System Generated Number

  • 0001333740