Kohlrausch law of independent migration of ions
E635554
The Kohlrausch law of independent migration of ions states that at infinite dilution, each ion contributes a characteristic, additive amount to the total molar conductivity of an electrolyte solution, independent of the other ions present.
Statements (45)
| Predicate | Object |
|---|---|
| instanceOf |
law in electrochemistry
ⓘ
physical law ⓘ |
| alsoKnownAs |
Kohlrausch’s law
NERFINISHED
ⓘ
Kohlrausch’s law of independent ionic migration NERFINISHED ⓘ |
| appliesTo |
aqueous electrolyte solutions
ⓘ
binary electrolytes ⓘ multi-ionic electrolytes at infinite dilution ⓘ strong electrolytes ⓘ |
| appliesUnderCondition | infinite dilution ⓘ |
| assumes |
ions do not interact with each other at infinite dilution
ⓘ
transport numbers are constant at infinite dilution ⓘ |
| concernsConcept | independent ionic migration ⓘ |
| concernsProperty | ionic molar conductivity at infinite dilution ⓘ |
| concernsQuantity |
limiting molar conductivity
ⓘ
molar conductivity ⓘ |
| concernsSpecies |
anions
ⓘ
cations ⓘ |
| field |
electrochemistry
ⓘ
physical chemistry ⓘ |
| hasConsequence |
ionic contributions to conductivity can be tabulated as constants
ⓘ
limiting molar conductivity of strong electrolytes increases with dilution ⓘ |
| implies | limiting molar conductivity of an electrolyte is additive in ionic contributions ⓘ |
| isFoundationFor | calculation of transference numbers from conductivity data ⓘ |
| limitation | ionic interactions become significant at higher concentrations ⓘ |
| mathematicalForm |
Λm∞ = λ+∞ + λ−∞ for a 1:1 electrolyte
ⓘ
Λm∞ = ν+ λ+∞ + ν− λ−∞ for a ν+:ν− electrolyte ⓘ |
| namedAfter | Friedrich Kohlrausch NERFINISHED ⓘ |
| notValidWhen | electrolyte concentration is high ⓘ |
| relatedTo |
Debye–Hückel theory
NERFINISHED
ⓘ
Onsager limiting law NERFINISHED ⓘ |
| relates | limiting molar conductivity of an electrolyte to limiting ionic conductivities ⓘ |
| requires | knowledge of ionic charges and stoichiometric coefficients of the electrolyte ⓘ |
| statesThat |
at infinite dilution each ion contributes a characteristic amount to the molar conductivity of an electrolyte
ⓘ
the molar conductivity at infinite dilution is the sum of independent ionic contributions ⓘ |
| supportsConcept | additivity of ionic conductances ⓘ |
| usedFor |
calculation of individual ionic conductivities
ⓘ
calculation of ionic mobilities ⓘ determination of degree of dissociation of weak electrolytes ⓘ determination of limiting molar conductivity of electrolytes ⓘ verification of strong electrolyte behavior at low concentration ⓘ |
| usedIn |
analysis of conductometric data
ⓘ
design of electrolyte solutions in electrochemical systems ⓘ teaching of undergraduate physical chemistry ⓘ |
| validWhen | electrolyte concentration approaches zero ⓘ |
| yearProposed | late 19th century ⓘ |
Referenced by (1)
Full triples — surface form annotated when it differs from this entity's canonical label.