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

# tantalum

| Property | Value |
| --- | --- |
| Symbol | Ta |
| Atomic number | 73 |
| IRI | `https://hendrikborgelt.github.io/Draft_for_IUPAC_CIAAW-Isotopic-Abundances-and-Atomic-Weights/elements/Tantalum` |
| Wikidata | [Q1123](https://www.wikidata.org/wiki/Q1123) |

## Standard atomic weight

| Value | Year | Source | Status | Declaration |
| --- | --- | --- | --- | --- |
| 180.947 88(2) | 2005 | [10.1351/pac200678112051](https://doi.org/10.1351/pac200678112051) | Current | [`AW-Ta-standard`](../id/AW-Ta-standard.md) |
| 180.9479(1) | 1979 | [10.1351/pac198052102349](https://doi.org/10.1351/pac198052102349) | Deprecated, see [`AW-Ta-standard`](../id/AW-Ta-standard.md) | [`AW-Ta-standard-1979`](../id/AW-Ta-standard-1979.md) |
| 180.9479(3) | 1969 | [10.1351/pac197021010091](https://doi.org/10.1351/pac197021010091) | Deprecated, see [`AW-Ta-standard-1979`](../id/AW-Ta-standard-1979.md) | [`AW-Ta-standard-1969`](../id/AW-Ta-standard-1969.md) |
| 180.948 | 1961 | [10.1021/ja00881a001](https://doi.org/10.1021/ja00881a001) | Deprecated, see [`AW-Ta-standard-1969`](../id/AW-Ta-standard-1969.md) | [`AW-Ta-standard-1961`](../id/AW-Ta-standard-1961.md) |
| 180.95 | 1953 | [10.1039/JR9540004713](https://doi.org/10.1039/JR9540004713) | Deprecated, see [`AW-Ta-standard-1961`](../id/AW-Ta-standard-1961.md) | [`AW-Ta-standard-1953`](../id/AW-Ta-standard-1953.md) |
| 180.88 | 1936 | [10.1039/JR9370001893](https://doi.org/10.1039/JR9370001893) | Deprecated, see [`AW-Ta-standard-1953`](../id/AW-Ta-standard-1953.md) | [`AW-Ta-standard-1936`](../id/AW-Ta-standard-1936.md) |
| 181.4 | 1931 | [10.1039/JR9310001617](https://doi.org/10.1039/JR9310001617) | Deprecated, see [`AW-Ta-standard-1936`](../id/AW-Ta-standard-1936.md) | [`AW-Ta-standard-1931`](../id/AW-Ta-standard-1931.md) |
| 181.5 | 1912 | [10.1021/ja02224a601](https://doi.org/10.1021/ja02224a601) | Deprecated, see [`AW-Ta-standard-1931`](../id/AW-Ta-standard-1931.md) | [`AW-Ta-standard-1912`](../id/AW-Ta-standard-1912.md) |
| 181 | 1909 | [10.1021/ja01931a001](https://doi.org/10.1021/ja01931a001) | Deprecated, see [`AW-Ta-standard-1912`](../id/AW-Ta-standard-1912.md) | [`AW-Ta-standard-1909`](../id/AW-Ta-standard-1909.md) |
| 181 | 1907 | [10.1021/ja01956a001](https://doi.org/10.1021/ja01956a001) | Deprecated, see [`AW-Ta-standard-1909`](../id/AW-Ta-standard-1909.md) | [`AW-Ta-standard-1907`](../id/AW-Ta-standard-1907.md) |
| 183 | 1902 | [10.1007/BF01370337](https://doi.org/10.1007/BF01370337) | Deprecated, see [`AW-Ta-standard-1907`](../id/AW-Ta-standard-1907.md) | [`AW-Ta-standard-1902`](../id/AW-Ta-standard-1902.md) |


## Isotopes

| A | Representative isotopic composition | Year | Source | Declaration | ChEBI | Wikidata |
| --- | --- | --- | --- | --- | --- | --- |
| [180](../id/Ta-180.md) | 0.000 1176(23) | — | — | [`Abundance-Ta180`](../id/Abundance-Ta180.md) | — | [Q18882795](https://www.wikidata.org/wiki/Q18882795) |
| [181](../id/Ta-181.md) | 0.999 8824(23) | — | — | [`Abundance-Ta181`](../id/Abundance-Ta181.md) | — | [Q18882801](https://www.wikidata.org/wiki/Q18882801) |

## 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 1979. (1980). <i>Pure and Applied Chemistry</i>, <i>52</i>(10), 2349–2384. https://doi.org/10.1351/pac198052102349 <a href="https://doi.org/10.1351/pac198052102349">CrossRef</a> <a href="https://qlever.scholia.wiki/doi/10.1351/pac198052102349">Scholia</a></div>
<div class="csl-entry">Baxter, G. P., Curie, Mme. M., Hönigschmid, O., Lebeau, P., &#38; Meyer, R. J. (1931). First Report of the Committee on the Atomic Weights of the International Union of Chemistry. <i>J. Chem. Soc.</i>, <i>0</i>(0), 1617–1627. https://doi.org/10.1039/jr9310001617 <a href="https://doi.org/10.1039/JR9310001617">CrossRef</a> <a href="https://qlever.scholia.wiki/doi/10.1039/JR9310001617">Scholia</a></div>
<div class="csl-entry">Cameron, A. E., &#38; Wichers, Edward. (1962). <b>Report of the International Commission on Atomic Weights<sup>*</sup>(1961)</b>. <i>Journal of the American Chemical Society</i>, <i>84</i>(22), 4175–4197. https://doi.org/10.1021/ja00881a001 <a href="https://doi.org/10.1021/ja00881a001">CrossRef</a> <a href="https://qlever.scholia.wiki/doi/10.1021/ja00881a001">Scholia</a></div>
<div class="csl-entry">Clarke, F. W., Ostwald, W., Thorpe, T. E., &#38; Urbain, G. (1909). REPORT OF THE INTERNATIONAL COMMITTEE ON ATOMIC WEIGHTS. 1909. <i>Journal of the American Chemical Society</i>, <i>31</i>(1), 1–6. https://doi.org/10.1021/ja01931a001 <a href="https://doi.org/10.1021/ja01931a001">CrossRef</a> <a href="https://qlever.scholia.wiki/doi/10.1021/ja01931a001">Scholia</a></div>
<div class="csl-entry">Clarke, F. W., Thorpe, T. E., Moissan, H., &#38; Ostwald, W. (1907). REPORT OF THE INTERNATIONAL COMMITTEE ON ATOMIC WEIGHTS. 1907. <i>Journal of the American Chemical Society</i>, <i>29</i>(2), 107–111. https://doi.org/10.1021/ja01956a001 <a href="https://doi.org/10.1021/ja01956a001">CrossRef</a> <a href="https://qlever.scholia.wiki/doi/10.1021/ja01956a001">Scholia</a></div>
<div class="csl-entry">Clarke, F., Thorpe, T., Ostwald, W., &#38; Urbain, G. (1911). Annual Report of the International Committee on Atomic Weights, 1912. <i>Journal of the American Chemical Society</i>, <i>33</i>(11), 1639–1642. https://doi.org/10.1021/ja02224a601 <a href="https://doi.org/10.1021/ja02224a601">CrossRef</a> <a href="https://qlever.scholia.wiki/doi/10.1021/ja02224a601">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">International atomic weights, 1953. (1954). <i>Journal of the Chemical Society (Resumed)</i>, 4713. https://doi.org/10.1039/jr9540004713 <a href="https://doi.org/10.1039/JR9540004713">CrossRef</a> <a href="https://qlever.scholia.wiki/doi/10.1039/JR9540004713">Scholia</a></div>
<div class="csl-entry">Richards, Baxter, Hinrichsen, Köthner, P., &#38; Pellini, S. (1902). Zur Festsetzung der Atomgewichte. <i>Fresenius’ Zeitschrift für analytische Chemie</i>, <i>41</i>(2), 139–140. https://doi.org/10.1007/bf01370337 <a href="https://doi.org/10.1007/BF01370337">CrossRef</a> <a href="https://qlever.scholia.wiki/doi/10.1007/BF01370337">Scholia</a></div>
<div class="csl-entry">Wieser, M. E. (2006). Atomic weights of the elements 2005 (IUPAC Technical Report). <i>Pure and Applied Chemistry</i>, <i>78</i>(11), 2051–2066. https://doi.org/10.1351/pac200678112051 <a href="https://doi.org/10.1351/pac200678112051">CrossRef</a> <a href="https://qlever.scholia.wiki/doi/10.1351/pac200678112051">Scholia</a></div>
</div>

## Turtle

This resource as a file: [Tantalum.ttl](Tantalum.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-Ta-standard-1902 a ciaaw:StandardAtomicWeightDeclaration ;
    dcterms:isReplacedBy ciaaw_draft:AW-Ta-standard-1907 ;
    dcterms:issued "1902"^^xsd:gYear ;
    dcterms:source <https://doi.org/10.1007/BF01370337> ;
    owl:deprecated true ;
    adms:status <http://purl.org/adms/status/Deprecated> ;
    ciaaw:ofElement element:Tantalum ;
    ciaaw:value [ a qudt:QuantityValue ;
            qudt:hasUnit unit:UNITLESS ;
            qudt:numericValue 183.0 ] .

ciaaw_draft:AW-Ta-standard a ciaaw:StandardAtomicWeightDeclaration ;
    dcterms:issued "2005"^^xsd:gYear ;
    dcterms:replaces ciaaw_draft:AW-Ta-standard-1979 ;
    dcterms:source <https://doi.org/10.1351/pac200678112051> ;
    ciaaw:ofElement element:Tantalum ;
    ciaaw:value [ a qudt:QuantityValue ;
            qudt:hasUnit unit:UNITLESS ;
            qudt:numericValue 180.94788 ;
            qudt:standardUncertainty 0.00002 ;
            ciaaw:significantFigures 8 ;
            ciaaw:significantFiguresUncertainty 1 ] .

ciaaw_draft:AW-Ta-standard-1907 a ciaaw:StandardAtomicWeightDeclaration ;
    dcterms:isReplacedBy ciaaw_draft:AW-Ta-standard-1909 ;
    dcterms:issued "1907"^^xsd:gYear ;
    dcterms:replaces ciaaw_draft:AW-Ta-standard-1902 ;
    dcterms:source <https://doi.org/10.1021/ja01956a001> ;
    owl:deprecated true ;
    adms:status <http://purl.org/adms/status/Deprecated> ;
    ciaaw:ofElement element:Tantalum ;
    ciaaw:value [ a qudt:QuantityValue ;
            qudt:hasUnit unit:UNITLESS ;
            qudt:numericValue 181.0 ] .

ciaaw_draft:AW-Ta-standard-1909 a ciaaw:StandardAtomicWeightDeclaration ;
    dcterms:isReplacedBy ciaaw_draft:AW-Ta-standard-1912 ;
    dcterms:issued "1909"^^xsd:gYear ;
    dcterms:replaces ciaaw_draft:AW-Ta-standard-1907 ;
    dcterms:source <https://doi.org/10.1021/ja01931a001> ;
    owl:deprecated true ;
    adms:status <http://purl.org/adms/status/Deprecated> ;
    ciaaw:ofElement element:Tantalum ;
    ciaaw:value [ a qudt:QuantityValue ;
            qudt:hasUnit unit:UNITLESS ;
            qudt:numericValue 181.0 ] .

ciaaw_draft:AW-Ta-standard-1912 a ciaaw:StandardAtomicWeightDeclaration ;
    dcterms:isReplacedBy ciaaw_draft:AW-Ta-standard-1931 ;
    dcterms:issued "1912"^^xsd:gYear ;
    dcterms:replaces ciaaw_draft:AW-Ta-standard-1909 ;
    dcterms:source <https://doi.org/10.1021/ja02224a601> ;
    owl:deprecated true ;
    adms:status <http://purl.org/adms/status/Deprecated> ;
    ciaaw:ofElement element:Tantalum ;
    ciaaw:value [ a qudt:QuantityValue ;
            qudt:hasUnit unit:UNITLESS ;
            qudt:numericValue 181.5 ] .

ciaaw_draft:AW-Ta-standard-1931 a ciaaw:StandardAtomicWeightDeclaration ;
    dcterms:isReplacedBy ciaaw_draft:AW-Ta-standard-1936 ;
    dcterms:issued "1931"^^xsd:gYear ;
    dcterms:replaces ciaaw_draft:AW-Ta-standard-1912 ;
    dcterms:source <https://doi.org/10.1039/JR9310001617> ;
    owl:deprecated true ;
    adms:status <http://purl.org/adms/status/Deprecated> ;
    ciaaw:ofElement element:Tantalum ;
    ciaaw:value [ a qudt:QuantityValue ;
            qudt:hasUnit unit:UNITLESS ;
            qudt:numericValue 181.4 ] .

ciaaw_draft:AW-Ta-standard-1936 a ciaaw:StandardAtomicWeightDeclaration ;
    dcterms:isReplacedBy ciaaw_draft:AW-Ta-standard-1953 ;
    dcterms:issued "1936"^^xsd:gYear ;
    dcterms:replaces ciaaw_draft:AW-Ta-standard-1931 ;
    dcterms:source <https://doi.org/10.1039/JR9370001893> ;
    owl:deprecated true ;
    adms:status <http://purl.org/adms/status/Deprecated> ;
    ciaaw:ofElement element:Tantalum ;
    ciaaw:value [ a qudt:QuantityValue ;
            qudt:hasUnit unit:UNITLESS ;
            qudt:numericValue 180.88 ] .

ciaaw_draft:AW-Ta-standard-1953 a ciaaw:StandardAtomicWeightDeclaration ;
    dcterms:isReplacedBy ciaaw_draft:AW-Ta-standard-1961 ;
    dcterms:issued "1953"^^xsd:gYear ;
    dcterms:replaces ciaaw_draft:AW-Ta-standard-1936 ;
    dcterms:source <https://doi.org/10.1039/JR9540004713> ;
    owl:deprecated true ;
    adms:status <http://purl.org/adms/status/Deprecated> ;
    ciaaw:ofElement element:Tantalum ;
    ciaaw:value [ a qudt:QuantityValue ;
            qudt:hasUnit unit:UNITLESS ;
            qudt:numericValue 180.95 ] .

ciaaw_draft:AW-Ta-standard-1961 a ciaaw:StandardAtomicWeightDeclaration ;
    dcterms:isReplacedBy ciaaw_draft:AW-Ta-standard-1969 ;
    dcterms:issued "1961"^^xsd:gYear ;
    dcterms:replaces ciaaw_draft:AW-Ta-standard-1953 ;
    dcterms:source <https://doi.org/10.1021/ja00881a001> ;
    owl:deprecated true ;
    adms:status <http://purl.org/adms/status/Deprecated> ;
    ciaaw:ofElement element:Tantalum ;
    ciaaw:value [ a qudt:QuantityValue ;
            qudt:hasUnit unit:UNITLESS ;
            qudt:numericValue 180.948 ] .

ciaaw_draft:AW-Ta-standard-1969 a ciaaw:StandardAtomicWeightDeclaration ;
    dcterms:isReplacedBy ciaaw_draft:AW-Ta-standard-1979 ;
    dcterms:issued "1969"^^xsd:gYear ;
    dcterms:replaces ciaaw_draft:AW-Ta-standard-1961 ;
    dcterms:source <https://doi.org/10.1351/pac197021010091> ;
    owl:deprecated true ;
    adms:status <http://purl.org/adms/status/Deprecated> ;
    ciaaw:ofElement element:Tantalum ;
    ciaaw:value [ a qudt:QuantityValue ;
            qudt:hasUnit unit:UNITLESS ;
            qudt:numericValue 180.9479 ;
            qudt:standardUncertainty 0.0003 ;
            ciaaw:significantFigures 7 ;
            ciaaw:significantFiguresUncertainty 1 ] .

ciaaw_draft:AW-Ta-standard-1979 a ciaaw:StandardAtomicWeightDeclaration ;
    dcterms:isReplacedBy ciaaw_draft:AW-Ta-standard ;
    dcterms:issued "1979"^^xsd:gYear ;
    dcterms:replaces ciaaw_draft:AW-Ta-standard-1969 ;
    dcterms:source <https://doi.org/10.1351/pac198052102349> ;
    owl:deprecated true ;
    adms:status <http://purl.org/adms/status/Deprecated> ;
    ciaaw:ofElement element:Tantalum ;
    ciaaw:value [ a qudt:QuantityValue ;
            qudt:hasUnit unit:UNITLESS ;
            qudt:numericValue 180.9479 ;
            qudt:standardUncertainty 0.0001 ;
            ciaaw:significantFigures 7 ;
            ciaaw:significantFiguresUncertainty 1 ] .

element:Tantalum a chemrof:ChemicalElement ;
    rdfs:label "tantalum"@en ;
    ciaaw:currentStandardAtomicWeight ciaaw_draft:AW-Ta-standard ;
    ciaaw:hasDeclaration ciaaw_draft:AW-Ta-standard,
        ciaaw_draft:AW-Ta-standard-1902,
        ciaaw_draft:AW-Ta-standard-1907,
        ciaaw_draft:AW-Ta-standard-1909,
        ciaaw_draft:AW-Ta-standard-1912,
        ciaaw_draft:AW-Ta-standard-1931,
        ciaaw_draft:AW-Ta-standard-1936,
        ciaaw_draft:AW-Ta-standard-1953,
        ciaaw_draft:AW-Ta-standard-1961,
        ciaaw_draft:AW-Ta-standard-1969,
        ciaaw_draft:AW-Ta-standard-1979 ;
    ciaaw:hasIsotope ciaaw_draft:Ta-180,
        ciaaw_draft:Ta-181 ;
    ciaaw:standardAtomicWeightUncertainty 0.00002 ;
    ciaaw:standardAtomicWeightValue 180.94788 ;
    chemrof:atomic_number 73 ;
    chemrof:symbol "Ta" .
```

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