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9-30

affinity of a chemical reaction

URNurn:iso:std:iso:80000:-9:ed-2:en:item:9-30

https://metanorma.github.io/isq-smart/quantities/part-9/t9-30
urn:iso:std:iso:80000:-9:ed-2:en:item:9-30

ISQ Identifiers

ISO

urn:iso:std:iso:80000:-9:ed-2:en:item:9-30

IEC

urn:iec:std:iec:80000-9:2019:::item:9-30

Designations

ENaffinity of a chemical reaction

FRaffinité d'une réaction chimique

Symbol

A

Notation systems

Rendered

A

AsciiMath

A

LaTeX

A

Definition

negative of the sum over all substances $B$ of products of stoichiometric number $ν_{B}$ of substance $B$ (stoichiometric number of substance) and chemical potential $μ_{B}$ of substance $B$ (chemical potential <chemistry>):

A = - \sum ν_{B} μ_{B}

négatif de la somme pour tous les constituants $B$ des produits du nombre stœchiométrique $ν_{B}$ du constituant $B$ (stoichiometric number of substance) et du potentiel chimique $μ_{B}$ du constituant $B$ (chemical potential <chemistry>):

A = - \sum ν_{B} μ_{B}

Units

\frac{J}{m} o l

joule per mole

View related quantities →

k g \cdot m^{2} \cdot s^{- 2} \cdot m o l^{- 1}

kilogram square metre per second squared mole

View related quantities →

Notes

The affinity of a reaction is a measure of the "driving force" of the reaction. When it is positive, the reaction goes spontaneously from reactants to products, and when it is negative, the reaction goes in the opposite direction. Another way to write the definition is:

A = {(\partial G / \partial ξ)}_{p, T}

where $G$ is Gibbs energy (ISO 80000-5: Thermodynamics) and $ξ$ is the extent of the reaction (extent of reaction).

Note that $ν_{B}$ is negative for reactants and positive for products.

L'affinité d'une réaction est une mesure de la «force d'entraînement» de la réaction. Lorsqu'elle est positive, la réaction a lieu spontanément des réactifs aux produits et lorsqu'elle est négative, la réaction a lieu dans l'autre sens. Une autre façon d'écrire la définition est:

A = {(\partial G / \partial ξ)}_{p, T}

où $G$ est l'enthalpie libre (ISO 80000-5: Thermodynamics) et $ξ$ est l'état d'avancement de la réaction (extent of reaction).

À noter que $ν_{B}$ est négatif pour les réactifs et positif pour les produits.

Referenced by

extent of reaction

Concept HierarchyPendrill (2024)

L² M T⁻² N⁻¹L² M T⁻² N⁻¹ quantitiesLevel 0 · Kind

Broader concepts

◇ L² M T⁻² N⁻¹ quantities

Characterizes

● 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:t9-30

Properties

isq:QuantityShape

Property	Value
rdf:type	isq:Quantity smart:TermEntry
dcterms:identifier	9-30
skosxl:prefLabel	"affinity of a chemical reaction"@en
skosxl:altLabel	"A"@en
skos:definition	negative of the sum over all substances stem:["B"] of products of stoichiometric number stem:[nu_"B"] of substance stem:…
skos:note	The affinity of a reaction is a measure of the "driving force" of the reaction. When it is positive, the reaction goes s…
isq:hasUnit	J/mol (joule per mole)kgm^2s^(-2)*mol^(-1) (kilogram square metre per second squared mole)
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