Hydron (chemistry)

Hydron

Names
Systematic IUPAC name Hydron[1] (substitutive) Hydrogen(1+)[1] (additive)
Other names Proton
Identifiers
CAS Number	12408-02-5 Y
3D model (JSmol)	Interactive image
ChEBI	CHEBI:15378
ChemSpider	1010 Y
IUPHAR/BPS	2346
KEGG	C00080 Y
PubChem CID	1038
UNII	5046UKT60S Y
CompTox Dashboard (EPA)	DTXSID50924722
InChI InChI=1S/p+1 Y Key: GPRLSGONYQIRFK-UHFFFAOYSA-N Y
SMILES [H+]
Properties
Chemical formula	H+
Molar mass	1.007 g·mol−1
Thermochemistry
Std molar entropy (S⦵298)	108.95 J K−1 mol−1
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

In chemistry, the hydron, informally called proton,^[2] is the cationic form of atomic hydrogen, represented with the symbol H⁺
. The general term "hydron", endorsed by IUPAC, encompasses cations of hydrogen regardless of isotope: thus it refers collectively to protons (¹H⁺) for the protium isotope, deuterons (²H⁺ or D⁺) for the deuterium isotope, and tritons (³H⁺ or T⁺) for the tritium isotope.

Unlike most other ions, the hydron consists only of a bare atomic nucleus. The negatively charged counterpart of the hydron is the hydride anion, H⁻
.