> **PROTOTYPE:** a suggestion, not an official CIAAW or IUPAC page. Official values are at [ciaaw.org](https://ciaaw.org). # hydrogen | Property | Value | | --- | --- | | Symbol | H | | Atomic number | 1 | | IRI | `https://hendrikborgelt.github.io/Draft_for_IUPAC_CIAAW-Isotopic-Abundances-and-Atomic-Weights/elements/Hydrogen` | | ChEBI | [CHEBI:49637](http://purl.obolibrary.org/obo/CHEBI_49637) | | Wikidata | [Q556](https://www.wikidata.org/wiki/Q556) | ## Standard atomic weight | Value | Year | Source | Status | Declaration | | --- | --- | --- | --- | --- | | [1.007 84, 1.008 11] | 2009 | [10.1351/PAC-REP-10-09-14](https://doi.org/10.1351/PAC-REP-10-09-14) | Current | [`AW-H-standard-2009`](../id/AW-H-standard-2009.md) | | 1.007 94(7) | 1981 | [10.1351/pac198355071101](https://doi.org/10.1351/pac198355071101) | Deprecated, see [`AW-H-standard-2009`](../id/AW-H-standard-2009.md) | [`AW-H-standard-1981`](../id/AW-H-standard-1981.md) | | 1.0079(1) | 1971 | [10.1351/pac197230030637](https://doi.org/10.1351/pac197230030637) | Deprecated, see [`AW-H-standard-1981`](../id/AW-H-standard-1981.md) | [`AW-H-standard-1971`](../id/AW-H-standard-1971.md) | | 1.0080(3) | 1969 | [10.1351/pac197021010091](https://doi.org/10.1351/pac197021010091) | Deprecated, see [`AW-H-standard-1971`](../id/AW-H-standard-1971.md) | [`AW-H-standard-1969`](../id/AW-H-standard-1969.md) | | 1.007 97(1) | 1961 | [10.1021/ja00881a001](https://doi.org/10.1021/ja00881a001) | Deprecated, see [`AW-H-standard-1969`](../id/AW-H-standard-1969.md) | [`AW-H-standard-1961`](../id/AW-H-standard-1961.md) | | 1.0080 | 1940 | [10.1039/JR9400000475](https://doi.org/10.1039/JR9400000475) | Deprecated, see [`AW-H-standard-1961`](../id/AW-H-standard-1961.md) | [`AW-H-standard-1940`](../id/AW-H-standard-1940.md) | | 1.0081 | 1938 | [10.1039/JR9380001101](https://doi.org/10.1039/JR9380001101) | Deprecated, see [`AW-H-standard-1940`](../id/AW-H-standard-1940.md) | [`AW-H-standard-1938`](../id/AW-H-standard-1938.md) | | 1.0078 | 1931 | [10.1039/JR9310001617](https://doi.org/10.1039/JR9310001617) | Deprecated, see [`AW-H-standard-1938`](../id/AW-H-standard-1938.md) | [`AW-H-standard-1931`](../id/AW-H-standard-1931.md) | | 1.008 | 1903 | [10.1021/ja02003a001](https://doi.org/10.1021/ja02003a001) | Deprecated, see [`AW-H-standard-1931`](../id/AW-H-standard-1931.md) | [`AW-H-standard-1903`](../id/AW-H-standard-1903.md) | | 1.01 | 1902 | [10.1007/BF01370337](https://doi.org/10.1007/BF01370337) | Deprecated, see [`AW-H-standard-1903`](../id/AW-H-standard-1903.md) | [`AW-H-standard-1902`](../id/AW-H-standard-1902.md) | Notes: [m](#note-m) ## Isotopes | A | Representative isotopic composition | Year | Source | Declaration | ChEBI | Wikidata | | --- | --- | --- | --- | --- | --- | --- | | [1](../id/H-1.md) | [0.999 72, 0.999 99] | — | [10.1515/pac-2015-0503](https://doi.org/10.1515/pac-2015-0503) | [`Abundance-H1`](../id/Abundance-H1.md) | [CHEBI:29236](http://purl.obolibrary.org/obo/CHEBI_29236) | [Q12830437](https://www.wikidata.org/wiki/Q12830437) | | [2](../id/H-2.md) | [0.000 01, 0.000 28] | 2016 | [10.1515/pac-2015-0503](https://doi.org/10.1515/pac-2015-0503) | [`Abundance-H2-2016`](../id/Abundance-H2-2016.md) | [CHEBI:29237](http://purl.obolibrary.org/obo/CHEBI_29237) | [Q102296](https://www.wikidata.org/wiki/Q102296) | Notes: [m](#note-m) ## Notes **m** Modified isotopic compositions may be found in commercially available material because the material has been subjected to some undisclosed or inadvertent isotopic fractionation. Substantial deviations in atomic weight of the element from that given in the table can occur. ## Bibliography
Atomic weights of the elements 1969. (1970). Pure and Applied Chemistry, 21(1), 91–108. https://doi.org/10.1351/pac197021010091 CrossRef Scholia
Atomic Weights of the Elements 1971. (1972). Pure and Applied Chemistry, 30(3–4), 637–650. https://doi.org/10.1351/pac197230030637 CrossRef Scholia
Baxter, G. P., Curie, Mme. M., Hönigschmid, O., Lebeau, P., & Meyer, R. J. (1931). First Report of the Committee on the Atomic Weights of the International Union of Chemistry. J. Chem. Soc., 0(0), 1617–1627. https://doi.org/10.1039/jr9310001617 CrossRef Scholia
Baxter, G. P., Guichard, M., Hönigschmid, O., & Whytlaw-Gray, R. (1940). Tenth Report of the Committee on Atomic Weights of the International Union of Chemistry. J. Chem. Soc., 0(0), 475–478. https://doi.org/10.1039/jr9400000475 CrossRef Scholia
Baxter, G. P., Hönigschmid, O., & Lebeau, P. (1938). Eighth Report of the Committee on Atomic Weights of the International Union of Chemistry. J. Chem. Soc., 0(0), 1101–1109. https://doi.org/10.1039/jr9380001101 CrossRef Scholia
Cameron, A. E., & Wichers, Edward. (1962). Report of the International Commission on Atomic Weights*(1961). Journal of the American Chemical Society, 84(22), 4175–4197. https://doi.org/10.1021/ja00881a001 CrossRef Scholia
Clarke, F. W. (1903). REPORT OF THE INTERNATIONAL COMMITTEE ON ATOMIC WEIGHTS. Journal of the American Chemical Society, 25(1), 1–5. https://doi.org/10.1021/ja02003a001 CrossRef Scholia
Holden, N. E., & Martin, R. L. (1983). Atomic weights of the elements 1981. Pure and Applied Chemistry, 55(7), 1101–1118. https://doi.org/10.1351/pac198355071101 CrossRef Scholia
Meija, J., Coplen, T. B., Berglund, M., Brand, W. A., De Bièvre, P., Gröning, M., Holden, N. E., Irrgeher, J., Loss, R. D., Walczyk, T., & Prohaska, T. (2016). Isotopic compositions of the elements 2013 (IUPAC Technical Report). Pure and Applied Chemistry, 88(3), 293–306. https://doi.org/10.1515/pac-2015-0503 CrossRef Scholia
Richards, Baxter, Hinrichsen, Köthner, P., & Pellini, S. (1902). Zur Festsetzung der Atomgewichte. Fresenius’ Zeitschrift für analytische Chemie, 41(2), 139–140. https://doi.org/10.1007/bf01370337 CrossRef Scholia
Wieser, M. E., & Coplen, T. B. (2010). Atomic weights of the elements 2009 (IUPAC Technical Report). Pure and Applied Chemistry, 83(2), 359–396. https://doi.org/10.1351/pac-rep-10-09-14 CrossRef Scholia
## Turtle This resource as a file: [Hydrogen.ttl](Hydrogen.ttl) ```turtle # Prototype: a suggestion, not an official CIAAW or IUPAC record. Official values are at https://ciaaw.org @prefix adms: . @prefix chebi: . @prefix chemrof: . @prefix ciaaw: . @prefix ciaaw_draft: . @prefix dcterms: . @prefix element: . @prefix owl: . @prefix qudt: . @prefix rdfs: . @prefix skos: . @prefix unit: . @prefix xsd: . ciaaw:note-m a ciaaw:Footnote ; skos:definition "Modified isotopic compositions may be found in commercially available material because the material has been subjected to some undisclosed or inadvertent isotopic fractionation. Substantial deviations in atomic weight of the element from that given in the table can occur."@en ; skos:notation "m" . ciaaw_draft:AW-H-standard-1902 a ciaaw:StandardAtomicWeightDeclaration ; dcterms:isReplacedBy ciaaw_draft:AW-H-standard-1903 ; dcterms:issued "1902"^^xsd:gYear ; dcterms:source ; owl:deprecated true ; adms:status ; ciaaw:ofElement element:Hydrogen ; ciaaw:value [ a qudt:QuantityValue ; qudt:hasUnit unit:UNITLESS ; qudt:numericValue 1.01 ] . ciaaw_draft:AW-H-standard-1903 a ciaaw:StandardAtomicWeightDeclaration ; dcterms:isReplacedBy ciaaw_draft:AW-H-standard-1931 ; dcterms:issued "1903"^^xsd:gYear ; dcterms:replaces ciaaw_draft:AW-H-standard-1902 ; dcterms:source ; owl:deprecated true ; adms:status ; ciaaw:ofElement element:Hydrogen ; ciaaw:value [ a qudt:QuantityValue ; qudt:hasUnit unit:UNITLESS ; qudt:numericValue 1.008 ] . ciaaw_draft:AW-H-standard-1931 a ciaaw:StandardAtomicWeightDeclaration ; dcterms:isReplacedBy ciaaw_draft:AW-H-standard-1938 ; dcterms:issued "1931"^^xsd:gYear ; dcterms:replaces ciaaw_draft:AW-H-standard-1903 ; dcterms:source ; owl:deprecated true ; adms:status ; ciaaw:ofElement element:Hydrogen ; ciaaw:value [ a qudt:QuantityValue ; qudt:hasUnit unit:UNITLESS ; qudt:numericValue 1.0078 ] . ciaaw_draft:AW-H-standard-1938 a ciaaw:StandardAtomicWeightDeclaration ; dcterms:isReplacedBy ciaaw_draft:AW-H-standard-1940 ; dcterms:issued "1938"^^xsd:gYear ; dcterms:replaces ciaaw_draft:AW-H-standard-1931 ; dcterms:source ; owl:deprecated true ; adms:status ; ciaaw:ofElement element:Hydrogen ; ciaaw:value [ a qudt:QuantityValue ; qudt:hasUnit unit:UNITLESS ; qudt:numericValue 1.0081 ] . ciaaw_draft:AW-H-standard-1940 a ciaaw:StandardAtomicWeightDeclaration ; dcterms:isReplacedBy ciaaw_draft:AW-H-standard-1961 ; dcterms:issued "1940"^^xsd:gYear ; dcterms:replaces ciaaw_draft:AW-H-standard-1938 ; dcterms:source ; owl:deprecated true ; adms:status ; ciaaw:ofElement element:Hydrogen ; ciaaw:value [ a qudt:QuantityValue ; qudt:hasUnit unit:UNITLESS ; qudt:numericValue 1.0080 ] . ciaaw_draft:AW-H-standard-1961 a ciaaw:StandardAtomicWeightDeclaration ; dcterms:isReplacedBy ciaaw_draft:AW-H-standard-1969 ; dcterms:issued "1961"^^xsd:gYear ; dcterms:replaces ciaaw_draft:AW-H-standard-1940 ; dcterms:source ; owl:deprecated true ; adms:status ; ciaaw:ofElement element:Hydrogen ; ciaaw:value [ a qudt:QuantityValue ; qudt:hasUnit unit:UNITLESS ; qudt:numericValue 1.00797 ; qudt:standardUncertainty 0.00001 ; ciaaw:significantFigures 6 ; ciaaw:significantFiguresUncertainty 1 ] . ciaaw_draft:AW-H-standard-1969 a ciaaw:StandardAtomicWeightDeclaration ; dcterms:isReplacedBy ciaaw_draft:AW-H-standard-1971 ; dcterms:issued "1969"^^xsd:gYear ; dcterms:replaces ciaaw_draft:AW-H-standard-1961 ; dcterms:source ; owl:deprecated true ; adms:status ; ciaaw:ofElement element:Hydrogen ; ciaaw:value [ a qudt:QuantityValue ; qudt:hasUnit unit:UNITLESS ; qudt:numericValue 1.0080 ; qudt:standardUncertainty 0.0003 ; ciaaw:significantFigures 5 ; ciaaw:significantFiguresUncertainty 1 ] . ciaaw_draft:AW-H-standard-1971 a ciaaw:StandardAtomicWeightDeclaration ; dcterms:isReplacedBy ciaaw_draft:AW-H-standard-1981 ; dcterms:issued "1971"^^xsd:gYear ; dcterms:replaces ciaaw_draft:AW-H-standard-1969 ; dcterms:source ; owl:deprecated true ; adms:status ; ciaaw:ofElement element:Hydrogen ; ciaaw:value [ a qudt:QuantityValue ; qudt:hasUnit unit:UNITLESS ; qudt:numericValue 1.0079 ; qudt:standardUncertainty 0.0001 ; ciaaw:significantFigures 5 ; ciaaw:significantFiguresUncertainty 1 ] . ciaaw_draft:AW-H-standard-1981 a ciaaw:StandardAtomicWeightDeclaration ; dcterms:isReplacedBy ciaaw_draft:AW-H-standard-2009 ; dcterms:issued "1981"^^xsd:gYear ; dcterms:replaces ciaaw_draft:AW-H-standard-1971 ; dcterms:source ; owl:deprecated true ; adms:status ; ciaaw:ofElement element:Hydrogen ; ciaaw:value [ a qudt:QuantityValue ; qudt:hasUnit unit:UNITLESS ; qudt:numericValue 1.00794 ; qudt:standardUncertainty 0.00007 ; ciaaw:significantFigures 6 ; ciaaw:significantFiguresUncertainty 1 ] . ciaaw_draft:AW-H-standard-2009 a ciaaw:StandardAtomicWeightDeclaration ; dcterms:issued "2009"^^xsd:gYear ; dcterms:replaces ciaaw_draft:AW-H-standard-1981 ; dcterms:source ; ciaaw:footnote ciaaw:note-m ; ciaaw:ofElement element:Hydrogen ; ciaaw:value [ a qudt:QuantityValue ; qudt:hasUnit unit:UNITLESS ; qudt:lowerBound 1.00784 ; qudt:upperBound 1.00811 ; ciaaw:significantFiguresLower 6 ; ciaaw:significantFiguresUpper 6 ] . element:Hydrogen a chemrof:ChemicalElement ; rdfs:label "hydrogen"@en ; skos:closeMatch chebi:49637 ; ciaaw:currentStandardAtomicWeight ciaaw_draft:AW-H-standard-2009 ; ciaaw:hasDeclaration ciaaw_draft:AW-H-standard-1902, ciaaw_draft:AW-H-standard-1903, ciaaw_draft:AW-H-standard-1931, ciaaw_draft:AW-H-standard-1938, ciaaw_draft:AW-H-standard-1940, ciaaw_draft:AW-H-standard-1961, ciaaw_draft:AW-H-standard-1969, ciaaw_draft:AW-H-standard-1971, ciaaw_draft:AW-H-standard-1981, ciaaw_draft:AW-H-standard-2009 ; ciaaw:hasIsotope ciaaw_draft:H-1, ciaaw_draft:H-2 ; ciaaw:standardAtomicWeightLower 1.00784 ; ciaaw:standardAtomicWeightUpper 1.00811 ; chemrof:atomic_number 1 ; chemrof:symbol "H" . ``` [All atomic weights](../atomic-weights.md) · [All isotopic abundances](../isotopic-abundances.md)