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9-13

amount-of-substance fraction, mole fraction

URNurn:iso:std:iso:80000:-9:ed-2:en:item:9-13

https://metanorma.github.io/isq-smart/quantities/part-9/t9-13
urn:iso:std:iso:80000:-9:ed-2:en:item:9-13

ISQ Identifiers

ISO

urn:iso:std:iso:80000:-9:ed-2:en:item:9-13

IEC

urn:iec:std:iec:80000-9:2019:::item:9-13

Designations

ENamount-of-substance fraction

FRfraction de quantité de matière

ENmole fraction

FRfraction molaire

Symbol

x_{X}

y_{X}

Notation systems

Rendered

x_{X}

Rendered

y_{X}

AsciiMath

x_"X"

AsciiMath

y_"X"

LaTeX

x_{\text{X}}

LaTeX

y_{\text{X}}

Definition

for substance $X$ in a mixture, quotient of amount of substance $n_{X}$ (amount of substance) of $X$ and total amount $n$ of substance (amount of substance) in the mixture:

x_{X} = n_{X} / n

pour un constituant $X$ d'un mélange, quotient de la quantité de matière $n_{X}$ (amount of substance) du constituant $X$ par la quantité de matière $n$ (amount of substance) totale dans le mélange:

x_{X} = n_{X} / n

Units

1

one

View related quantities →

Notes

For condensed phases, $x_{X}$ is used, and for gaseous mixtures $y_{X}$ may be used.

The unsystematic name "mole fraction" is still used. However, the use of this name is deprecated.

For this quantity, the entity used to define the amount of substance should always be a single molecule for every species in the mixture.

Pour des phases condensées, $x_{X}$ est utilisé, et pour des mélanges gazeux, $y_{X}$ peut être utilisé.

En anglais, le nom «mole fraction» est encore en usage, mais son utilisation est cependant à éviter.

Pour cette grandeur, il convient que l'entité utilisée pour définir la quantité de matière soit toujours une seule molécule pour toutes les espèces dans le mélange.

Referenced by

volume fraction partial pressure activity factor thermal diffusion ratio thermal diffusion factor

Concept HierarchyPendrill (2024)

1dimensionless quantitiesLevel 0 · Kind

Broader concepts

◇ dimensionless quantities

Characterizes

● molecule● substance

Ontology
isq:Quantity smart:TermEntry

Class Hierarchy

smart:Entity smart:TermEntryisq:Quantity

A physical quantity as defined in ISO/IEC 80000, with associated symbols, definitions, and units of measurement.

Instance IRI

isq:t9-13

Properties

isq:QuantityShape

Property	Value
rdf:type	isq:Quantity smart:TermEntry
dcterms:identifier	9-13
skosxl:prefLabel	"amount-of-substance fraction"@en
skosxl:altLabel	"mole fraction"@en"x_"X""@en"y_"X""@en
skos:definition	for substance stem:["X"] in a mixture, quotient of amount of substance stem:[n_"X"] (<<t9-2>>) of stem:["X"] and total a…
skos:note	For condensed phases, stem:[x_"X"] is used, and for gaseous mixtures stem:[y_"X"] may be used. The unsystematic name "m…
isq:hasUnit	1 (one)
isq:hasDimension	isq:Dimension
smart:hasBindingnessType	bindingness-type:normative
dcterms:isPartOf	isq:part-9

Related Entities

isq:QuantityShape isq:part-9 isq:Unit isq:Dimension isq:hasDimension smart:TermEntry