> **PROTOTYPE:** a suggestion, not an official CIAAW or IUPAC page. Official values are at [ciaaw.org](https://ciaaw.org).

# protactinium

| Property | Value |
| --- | --- |
| Symbol | Pa |
| Atomic number | 91 |
| IRI | `https://hendrikborgelt.github.io/Draft_for_IUPAC_CIAAW-Isotopic-Abundances-and-Atomic-Weights/elements/Protactinium` |
| Wikidata | [Q1109](https://www.wikidata.org/wiki/Q1109) |

## Standard atomic weight

| Value | Year | Source | Status | Declaration |
| --- | --- | --- | --- | --- |
| 231.035 88(1) | 2017 | [10.1515/pac-2019-0603](https://doi.org/10.1515/pac-2019-0603) | Current | [`AW-Pa-standard`](../id/AW-Pa-standard.md) |
| 231.035 88(2) | 1989 | [10.1351/pac199163070975](https://doi.org/10.1351/pac199163070975) | Deprecated, see [`AW-Pa-standard`](../id/AW-Pa-standard.md) | [`AW-Pa-standard-1989`](../id/AW-Pa-standard-1989.md) |
| 231.035 88(2) | 1985 | [10.1351/pac198658121677](https://doi.org/10.1351/pac198658121677) | Deprecated, see [`AW-Pa-standard-1989`](../id/AW-Pa-standard-1989.md) | [`AW-Pa-standard-1985`](../id/AW-Pa-standard-1985.md) |
| 231.0359(1) | 1969 | [10.1351/pac197021010091](https://doi.org/10.1351/pac197021010091) | Deprecated, see [`AW-Pa-standard-1985`](../id/AW-Pa-standard-1985.md) | [`AW-Pa-standard-1969`](../id/AW-Pa-standard-1969.md) |
| 231 | 1936 | [10.1039/JR9370001893](https://doi.org/10.1039/JR9370001893) | Deprecated, see [`AW-Pa-standard-1969`](../id/AW-Pa-standard-1969.md) | [`AW-Pa-standard-1936`](../id/AW-Pa-standard-1936.md) |


## Isotopes

| A | Representative isotopic composition | Year | Source | Declaration | ChEBI | Wikidata |
| --- | --- | --- | --- | --- | --- | --- |
| [231](../id/Pa-231.md) | 1 | — | — | [`Abundance-Pa231`](../id/Abundance-Pa231.md) | — | [Q18845514](https://www.wikidata.org/wiki/Q18845514) |

## Bibliography

<div class="csl-bib-body">
<div class="csl-entry">Atomic weights of the elements 1969. (1970). <i>Pure and Applied Chemistry</i>, <i>21</i>(1), 91–108. https://doi.org/10.1351/pac197021010091 <a href="https://doi.org/10.1351/pac197021010091">CrossRef</a> <a href="https://qlever.scholia.wiki/doi/10.1351/pac197021010091">Scholia</a></div>
<div class="csl-entry">Atomic weights of the elements 1985. (1986). <i>Pure and Applied Chemistry</i>, <i>58</i>(12), 1677–1692. https://doi.org/10.1351/pac198658121677 <a href="https://doi.org/10.1351/pac198658121677">CrossRef</a> <a href="https://qlever.scholia.wiki/doi/10.1351/pac198658121677">Scholia</a></div>
<div class="csl-entry">Atomic weights of the elements 1989. (1991). <i>Pure and Applied Chemistry</i>, <i>63</i>(7), 975–990. https://doi.org/10.1351/pac199163070975 <a href="https://doi.org/10.1351/pac199163070975">CrossRef</a> <a href="https://qlever.scholia.wiki/doi/10.1351/pac199163070975">Scholia</a></div>
<div class="csl-entry">Hönigschmid, O., &#38; Lebeau, P. (1937). Sixth Report of the Committee on Atomic Weights of the International Union of Chemistry. <i>J. Chem. Soc.</i>, <i>0</i>(0), 1893–1900. https://doi.org/10.1039/jr9370001893 <a href="https://doi.org/10.1039/JR9370001893">CrossRef</a> <a href="https://qlever.scholia.wiki/doi/10.1039/JR9370001893">Scholia</a></div>
<div class="csl-entry">Prohaska, T., Irrgeher, J., Benefield, J., Böhlke, J. K., Chesson, L. A., Coplen, T. B., Ding, T., Dunn, P. J. H., Gröning, M., Holden, N. E., Meijer, H. A. J., Moossen, H., Possolo, A., Takahashi, Y., Vogl, J., Walczyk, T., Wang, J., Wieser, M. E., Yoneda, S., … Meija, J. (2022). Standard atomic weights of the elements 2021 (IUPAC Technical Report). <i>Pure and Applied Chemistry</i>, <i>94</i>(5), 573–600. https://doi.org/10.1515/pac-2019-0603 <a href="https://doi.org/10.1515/pac-2019-0603">CrossRef</a> <a href="https://qlever.scholia.wiki/doi/10.1515/pac-2019-0603">Scholia</a></div>
</div>

## Turtle

This resource as a file: [Protactinium.ttl](Protactinium.ttl)

```turtle
# Prototype: a suggestion, not an official CIAAW or IUPAC record. Official values are at https://ciaaw.org

@prefix adms: <http://www.w3.org/ns/adms#> .
@prefix chemrof: <https://w3id.org/chemrof/> .
@prefix ciaaw: <https://hendrikborgelt.github.io/Draft_for_IUPAC_CIAAW-Isotopic-Abundances-and-Atomic-Weights/ciaaw-draft#> .
@prefix ciaaw_draft: <https://hendrikborgelt.github.io/Draft_for_IUPAC_CIAAW-Isotopic-Abundances-and-Atomic-Weights/id/> .
@prefix dcterms: <http://purl.org/dc/terms/> .
@prefix element: <https://hendrikborgelt.github.io/Draft_for_IUPAC_CIAAW-Isotopic-Abundances-and-Atomic-Weights/elements/> .
@prefix owl: <http://www.w3.org/2002/07/owl#> .
@prefix qudt: <http://qudt.org/schema/qudt/> .
@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .
@prefix unit: <http://qudt.org/vocab/unit/> .
@prefix xsd: <http://www.w3.org/2001/XMLSchema#> .

ciaaw_draft:AW-Pa-standard-1936 a ciaaw:StandardAtomicWeightDeclaration ;
    dcterms:isReplacedBy ciaaw_draft:AW-Pa-standard-1969 ;
    dcterms:issued "1936"^^xsd:gYear ;
    dcterms:source <https://doi.org/10.1039/JR9370001893> ;
    owl:deprecated true ;
    adms:status <http://purl.org/adms/status/Deprecated> ;
    ciaaw:ofElement element:Protactinium ;
    ciaaw:value [ a qudt:QuantityValue ;
            qudt:hasUnit unit:UNITLESS ;
            qudt:numericValue 231.0 ] .

ciaaw_draft:AW-Pa-standard a ciaaw:StandardAtomicWeightDeclaration ;
    dcterms:issued "2017"^^xsd:gYear ;
    dcterms:replaces ciaaw_draft:AW-Pa-standard-1989 ;
    dcterms:source <https://doi.org/10.1515/pac-2019-0603> ;
    ciaaw:ofElement element:Protactinium ;
    ciaaw:value [ a qudt:QuantityValue ;
            qudt:hasUnit unit:UNITLESS ;
            qudt:numericValue 231.03588 ;
            qudt:standardUncertainty 0.00001 ;
            ciaaw:significantFigures 8 ;
            ciaaw:significantFiguresUncertainty 1 ] .

ciaaw_draft:AW-Pa-standard-1969 a ciaaw:StandardAtomicWeightDeclaration ;
    dcterms:isReplacedBy ciaaw_draft:AW-Pa-standard-1985 ;
    dcterms:issued "1969"^^xsd:gYear ;
    dcterms:replaces ciaaw_draft:AW-Pa-standard-1936 ;
    dcterms:source <https://doi.org/10.1351/pac197021010091> ;
    owl:deprecated true ;
    adms:status <http://purl.org/adms/status/Deprecated> ;
    ciaaw:ofElement element:Protactinium ;
    ciaaw:value [ a qudt:QuantityValue ;
            qudt:hasUnit unit:UNITLESS ;
            qudt:numericValue 231.0359 ;
            qudt:standardUncertainty 0.0001 ;
            ciaaw:significantFigures 7 ;
            ciaaw:significantFiguresUncertainty 1 ] .

ciaaw_draft:AW-Pa-standard-1985 a ciaaw:StandardAtomicWeightDeclaration ;
    dcterms:isReplacedBy ciaaw_draft:AW-Pa-standard-1989 ;
    dcterms:issued "1985"^^xsd:gYear ;
    dcterms:replaces ciaaw_draft:AW-Pa-standard-1969 ;
    dcterms:source <https://doi.org/10.1351/pac198658121677> ;
    owl:deprecated true ;
    adms:status <http://purl.org/adms/status/Deprecated> ;
    ciaaw:ofElement element:Protactinium ;
    ciaaw:value [ a qudt:QuantityValue ;
            qudt:hasUnit unit:UNITLESS ;
            qudt:numericValue 231.03588 ;
            qudt:standardUncertainty 0.00002 ;
            ciaaw:significantFigures 8 ;
            ciaaw:significantFiguresUncertainty 1 ] .

ciaaw_draft:AW-Pa-standard-1989 a ciaaw:StandardAtomicWeightDeclaration ;
    dcterms:isReplacedBy ciaaw_draft:AW-Pa-standard ;
    dcterms:issued "1989"^^xsd:gYear ;
    dcterms:replaces ciaaw_draft:AW-Pa-standard-1985 ;
    dcterms:source <https://doi.org/10.1351/pac199163070975> ;
    owl:deprecated true ;
    adms:status <http://purl.org/adms/status/Deprecated> ;
    ciaaw:ofElement element:Protactinium ;
    ciaaw:value [ a qudt:QuantityValue ;
            qudt:hasUnit unit:UNITLESS ;
            qudt:numericValue 231.03588 ;
            qudt:standardUncertainty 0.00002 ;
            ciaaw:significantFigures 8 ;
            ciaaw:significantFiguresUncertainty 1 ] .

element:Protactinium a chemrof:ChemicalElement ;
    rdfs:label "protactinium"@en ;
    ciaaw:currentStandardAtomicWeight ciaaw_draft:AW-Pa-standard ;
    ciaaw:hasDeclaration ciaaw_draft:AW-Pa-standard,
        ciaaw_draft:AW-Pa-standard-1936,
        ciaaw_draft:AW-Pa-standard-1969,
        ciaaw_draft:AW-Pa-standard-1985,
        ciaaw_draft:AW-Pa-standard-1989 ;
    ciaaw:hasIsotope ciaaw_draft:Pa-231 ;
    ciaaw:standardAtomicWeightUncertainty 0.00001 ;
    ciaaw:standardAtomicWeightValue 231.03588 ;
    chemrof:atomic_number 91 ;
    chemrof:symbol "Pa" .
```

[All atomic weights](../atomic-weights.md) · [All isotopic abundances](../isotopic-abundances.md)