The mole was redefined in 2019 using an exact numerical value for the Avogadro constant

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SUPPORTED

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Is it true that the mole was redefined in 2019 using an exact numerical value for the Avogadro constant?

Yes. The mole was officially redefined in May 2019 by fixing the Avogadro constant to an exact numerical value.

Verdict: SUPPORTED · 2 sources for, 0 against · Last checked 31 Jul 2026

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Evidence for · 2

Wikipedia: Avogadro constant

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Wikipedia: Avogadro constant. (n.d.). Wikipedia. https://en.wikipedia.org/wiki/Avogadro_constant

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Wikipedia: 2019 revision of the SI

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Wikipedia: 2019 revision of the SI. (n.d.). Wikipedia. https://en.wikipedia.org/wiki/2019_revision_of_the_SI

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en.wikipedia.org: 2019 revision of the SI

Explicitly states that in 2019 the mole was defined by setting an exact numerical value for the Avogadro constant.

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en.wikipedia.org: 2019 revision of the SI. (n.d.). en.wikipedia.org. https://en.wikipedia.org/wiki/2019_revision_of_the_SI

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first checked31 Jul 2026

judged → SUPPORTED · 7531 Jul 2026

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