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

# silicon

| Property | Value |
| --- | --- |
| Symbol | Si |
| Atomic number | 14 |
| IRI | `https://hendrikborgelt.github.io/Draft_for_IUPAC_CIAAW-Isotopic-Abundances-and-Atomic-Weights/elements/Silicon` |
| Wikidata | [Q670](https://www.wikidata.org/wiki/Q670) |

## Standard atomic weight

| Value | Year | Source | Status | Declaration |
| --- | --- | --- | --- | --- |
| [28.084, 28.086] | 2009 | [10.1351/PAC-REP-10-09-14](https://doi.org/10.1351/PAC-REP-10-09-14) | Current | [`AW-Si-standard`](../id/AW-Si-standard.md) |
| 28.0855(3) | 1975 | [10.1351/pac197647010075](https://doi.org/10.1351/pac197647010075) | Deprecated, see [`AW-Si-standard`](../id/AW-Si-standard.md) | [`AW-Si-standard-1975`](../id/AW-Si-standard-1975.md) |
| 28.086(3) | 1969 | [10.1351/pac197021010091](https://doi.org/10.1351/pac197021010091) | Deprecated, see [`AW-Si-standard-1975`](../id/AW-Si-standard-1975.md) | [`AW-Si-standard-1969`](../id/AW-Si-standard-1969.md) |
| 28.086(1) | 1961 | [10.1021/ja00881a001](https://doi.org/10.1021/ja00881a001) | Deprecated, see [`AW-Si-standard-1969`](../id/AW-Si-standard-1969.md) | [`AW-Si-standard-1961`](../id/AW-Si-standard-1961.md) |
| 28.09 | 1951 | [10.1039/JR9530000001](https://doi.org/10.1039/JR9530000001) | Deprecated, see [`AW-Si-standard-1961`](../id/AW-Si-standard-1961.md) | [`AW-Si-standard-1951`](../id/AW-Si-standard-1951.md) |
| 28.06 | 1925 | [10.1039/CT9252700913](https://doi.org/10.1039/CT9252700913) | Deprecated, see [`AW-Si-standard-1951`](../id/AW-Si-standard-1951.md) | [`AW-Si-standard-1925`](../id/AW-Si-standard-1925.md) |
| 28.1 | 1922 | [10.1021/ja01441a001](https://doi.org/10.1021/ja01441a001) | Deprecated, see [`AW-Si-standard-1925`](../id/AW-Si-standard-1925.md) | [`AW-Si-standard-1922`](../id/AW-Si-standard-1922.md) |
| 28.3 | 1909 | [10.1021/ja01931a001](https://doi.org/10.1021/ja01931a001) | Deprecated, see [`AW-Si-standard-1922`](../id/AW-Si-standard-1922.md) | [`AW-Si-standard-1909`](../id/AW-Si-standard-1909.md) |
| 28.4 | 1902 | [10.1007/BF01370337](https://doi.org/10.1007/BF01370337) | Deprecated, see [`AW-Si-standard-1909`](../id/AW-Si-standard-1909.md) | [`AW-Si-standard-1902`](../id/AW-Si-standard-1902.md) |


## Isotopes

| A | Representative isotopic composition | Year | Source | Declaration | ChEBI | Wikidata |
| --- | --- | --- | --- | --- | --- | --- |
| [28](../id/Si-28.md) | [0.921 91, 0.923 18] | — | — | [`Abundance-Si28`](../id/Abundance-Si28.md) | — | [Q2236831](https://www.wikidata.org/wiki/Q2236831) |
| [29](../id/Si-29.md) | [0.046 45, 0.046 99] | — | — | [`Abundance-Si29`](../id/Abundance-Si29.md) | — | [Q3410389](https://www.wikidata.org/wiki/Q3410389) |
| [30](../id/Si-30.md) | [0.030 37, 0.031 10] | — | — | [`Abundance-Si30`](../id/Abundance-Si30.md) | — | [Q14338840](https://www.wikidata.org/wiki/Q14338840) |

## Bibliography

<div class="csl-bib-body">
<div class="csl-entry">(1976). <i>Pure and Applied Chemistry</i>, <i>47</i>(1), 75–96. https://doi.org/10.1351/pac197647010075 <a href="https://doi.org/10.1351/pac197647010075">CrossRef</a> <a href="https://qlever.scholia.wiki/doi/10.1351/pac197647010075">Scholia</a></div>
<div class="csl-entry">Aston, F. W., Baxter, G. P., Brauner, B., Debierne, A., Leduc, A., Richards, T. W., Soddy, F., &#38; Urbain, G. (1925). Second Report of the International Committee of the International Union of Pure and Applied Chemistry on the chemical elements. International atomic weights, 1925. <i>Journal of the Chemical Society, Transactions</i>, <i>127</i>, 913. https://doi.org/10.1039/ct9252700913 <a href="https://doi.org/10.1039/CT9252700913">CrossRef</a> <a href="https://qlever.scholia.wiki/doi/10.1039/CT9252700913">Scholia</a></div>
<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">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">International atomic weights, 1951. (1953). <i>Journal of the Chemical Society (Resumed)</i>, 1. https://doi.org/10.1039/jr9530000001 <a href="https://doi.org/10.1039/JR9530000001">CrossRef</a> <a href="https://qlever.scholia.wiki/doi/10.1039/JR9530000001">Scholia</a></div>
<div class="csl-entry">REPORT OF THE INTERNATIONAL COMMITTEE ON ATOMIC WEIGHTS FOR 1921-22. (1921). <i>Journal of the American Chemical Society</i>, <i>43</i>(8), [1751]-1753. https://doi.org/10.1021/ja01441a001 <a href="https://doi.org/10.1021/ja01441a001">CrossRef</a> <a href="https://qlever.scholia.wiki/doi/10.1021/ja01441a001">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., &#38; Coplen, T. B. (2010). Atomic weights of the elements 2009 (IUPAC Technical Report). <i>Pure and Applied Chemistry</i>, <i>83</i>(2), 359–396. https://doi.org/10.1351/pac-rep-10-09-14 <a href="https://doi.org/10.1351/PAC-REP-10-09-14">CrossRef</a> <a href="https://qlever.scholia.wiki/doi/10.1351/PAC-REP-10-09-14">Scholia</a></div>
</div>

## Turtle

This resource as a file: [Silicon.ttl](Silicon.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-Si-standard-1902 a ciaaw:StandardAtomicWeightDeclaration ;
    dcterms:isReplacedBy ciaaw_draft:AW-Si-standard-1909 ;
    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:Silicon ;
    ciaaw:value [ a qudt:QuantityValue ;
            qudt:hasUnit unit:UNITLESS ;
            qudt:numericValue 28.4 ] .

ciaaw_draft:AW-Si-standard a ciaaw:StandardAtomicWeightDeclaration ;
    dcterms:issued "2009"^^xsd:gYear ;
    dcterms:replaces ciaaw_draft:AW-Si-standard-1975 ;
    dcterms:source <https://doi.org/10.1351/PAC-REP-10-09-14> ;
    ciaaw:ofElement element:Silicon ;
    ciaaw:value [ a qudt:QuantityValue ;
            qudt:hasUnit unit:UNITLESS ;
            qudt:lowerBound 28.084 ;
            qudt:upperBound 28.086 ;
            ciaaw:significantFiguresLower 5 ;
            ciaaw:significantFiguresUpper 5 ] .

ciaaw_draft:AW-Si-standard-1909 a ciaaw:StandardAtomicWeightDeclaration ;
    dcterms:isReplacedBy ciaaw_draft:AW-Si-standard-1922 ;
    dcterms:issued "1909"^^xsd:gYear ;
    dcterms:replaces ciaaw_draft:AW-Si-standard-1902 ;
    dcterms:source <https://doi.org/10.1021/ja01931a001> ;
    owl:deprecated true ;
    adms:status <http://purl.org/adms/status/Deprecated> ;
    ciaaw:ofElement element:Silicon ;
    ciaaw:value [ a qudt:QuantityValue ;
            qudt:hasUnit unit:UNITLESS ;
            qudt:numericValue 28.3 ] .

ciaaw_draft:AW-Si-standard-1922 a ciaaw:StandardAtomicWeightDeclaration ;
    dcterms:isReplacedBy ciaaw_draft:AW-Si-standard-1925 ;
    dcterms:issued "1922"^^xsd:gYear ;
    dcterms:replaces ciaaw_draft:AW-Si-standard-1909 ;
    dcterms:source <https://doi.org/10.1021/ja01441a001> ;
    owl:deprecated true ;
    adms:status <http://purl.org/adms/status/Deprecated> ;
    ciaaw:ofElement element:Silicon ;
    ciaaw:value [ a qudt:QuantityValue ;
            qudt:hasUnit unit:UNITLESS ;
            qudt:numericValue 28.1 ] .

ciaaw_draft:AW-Si-standard-1925 a ciaaw:StandardAtomicWeightDeclaration ;
    dcterms:isReplacedBy ciaaw_draft:AW-Si-standard-1951 ;
    dcterms:issued "1925"^^xsd:gYear ;
    dcterms:replaces ciaaw_draft:AW-Si-standard-1922 ;
    dcterms:source <https://doi.org/10.1039/CT9252700913> ;
    owl:deprecated true ;
    adms:status <http://purl.org/adms/status/Deprecated> ;
    ciaaw:ofElement element:Silicon ;
    ciaaw:value [ a qudt:QuantityValue ;
            qudt:hasUnit unit:UNITLESS ;
            qudt:numericValue 28.06 ] .

ciaaw_draft:AW-Si-standard-1951 a ciaaw:StandardAtomicWeightDeclaration ;
    dcterms:isReplacedBy ciaaw_draft:AW-Si-standard-1961 ;
    dcterms:issued "1951"^^xsd:gYear ;
    dcterms:replaces ciaaw_draft:AW-Si-standard-1925 ;
    dcterms:source <https://doi.org/10.1039/JR9530000001> ;
    owl:deprecated true ;
    adms:status <http://purl.org/adms/status/Deprecated> ;
    ciaaw:ofElement element:Silicon ;
    ciaaw:value [ a qudt:QuantityValue ;
            qudt:hasUnit unit:UNITLESS ;
            qudt:numericValue 28.09 ] .

ciaaw_draft:AW-Si-standard-1961 a ciaaw:StandardAtomicWeightDeclaration ;
    dcterms:isReplacedBy ciaaw_draft:AW-Si-standard-1969 ;
    dcterms:issued "1961"^^xsd:gYear ;
    dcterms:replaces ciaaw_draft:AW-Si-standard-1951 ;
    dcterms:source <https://doi.org/10.1021/ja00881a001> ;
    owl:deprecated true ;
    adms:status <http://purl.org/adms/status/Deprecated> ;
    ciaaw:ofElement element:Silicon ;
    ciaaw:value [ a qudt:QuantityValue ;
            qudt:hasUnit unit:UNITLESS ;
            qudt:numericValue 28.086 ;
            qudt:standardUncertainty 0.001 ;
            ciaaw:significantFigures 5 ;
            ciaaw:significantFiguresUncertainty 1 ] .

ciaaw_draft:AW-Si-standard-1969 a ciaaw:StandardAtomicWeightDeclaration ;
    dcterms:isReplacedBy ciaaw_draft:AW-Si-standard-1975 ;
    dcterms:issued "1969"^^xsd:gYear ;
    dcterms:replaces ciaaw_draft:AW-Si-standard-1961 ;
    dcterms:source <https://doi.org/10.1351/pac197021010091> ;
    owl:deprecated true ;
    adms:status <http://purl.org/adms/status/Deprecated> ;
    ciaaw:ofElement element:Silicon ;
    ciaaw:value [ a qudt:QuantityValue ;
            qudt:hasUnit unit:UNITLESS ;
            qudt:numericValue 28.086 ;
            qudt:standardUncertainty 0.003 ;
            ciaaw:significantFigures 5 ;
            ciaaw:significantFiguresUncertainty 1 ] .

ciaaw_draft:AW-Si-standard-1975 a ciaaw:StandardAtomicWeightDeclaration ;
    dcterms:isReplacedBy ciaaw_draft:AW-Si-standard ;
    dcterms:issued "1975"^^xsd:gYear ;
    dcterms:replaces ciaaw_draft:AW-Si-standard-1969 ;
    dcterms:source <https://doi.org/10.1351/pac197647010075> ;
    owl:deprecated true ;
    adms:status <http://purl.org/adms/status/Deprecated> ;
    ciaaw:ofElement element:Silicon ;
    ciaaw:value [ a qudt:QuantityValue ;
            qudt:hasUnit unit:UNITLESS ;
            qudt:numericValue 28.0855 ;
            qudt:standardUncertainty 0.0003 ;
            ciaaw:significantFigures 6 ;
            ciaaw:significantFiguresUncertainty 1 ] .

element:Silicon a chemrof:ChemicalElement ;
    rdfs:label "silicon"@en ;
    ciaaw:currentStandardAtomicWeight ciaaw_draft:AW-Si-standard ;
    ciaaw:hasDeclaration ciaaw_draft:AW-Si-standard,
        ciaaw_draft:AW-Si-standard-1902,
        ciaaw_draft:AW-Si-standard-1909,
        ciaaw_draft:AW-Si-standard-1922,
        ciaaw_draft:AW-Si-standard-1925,
        ciaaw_draft:AW-Si-standard-1951,
        ciaaw_draft:AW-Si-standard-1961,
        ciaaw_draft:AW-Si-standard-1969,
        ciaaw_draft:AW-Si-standard-1975 ;
    ciaaw:hasIsotope ciaaw_draft:Si-28,
        ciaaw_draft:Si-29,
        ciaaw_draft:Si-30 ;
    ciaaw:standardAtomicWeightLower 28.084 ;
    ciaaw:standardAtomicWeightUpper 28.086 ;
    chemrof:atomic_number 14 ;
    chemrof:symbol "Si" .
```

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