van der Waals equation of state
E926078
The van der Waals equation of state is a thermodynamic equation that improves on the ideal gas law by accounting for the finite size of molecules and the intermolecular forces between them.
All labels observed (1)
| Label | Occurrences |
|---|---|
| van der Waals equation of state canonical | 1 |
How this entity was disambiguated
This entity first appeared as the object of triple T11436310 — resolving that mention is where its identity was fixed. The disambiguator weighed these candidate entities and picked the highlighted one (or “None”, minting a new entity). This is how homonymy is resolved: the same surface form can point to different entities.
NED1
Entity disambiguation (via context triple)
gpt-5-mini-2025-08-07
Target entity: van der Waals equation of state Context triple: [Johannes Diderik van der Waals, knownFor, van der Waals equation of state]
-
A.
Ornstein–Zernike equation
The Ornstein–Zernike equation is a fundamental relation in statistical mechanics that links the total and direct correlation functions of a fluid, forming the basis for many liquid-state theories and approximations.
-
B.
Clausius–Clapeyron relation
The Clausius–Clapeyron relation is a fundamental thermodynamic equation that describes how the pressure and temperature of a phase transition, such as boiling or condensation, are related.
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C.
Sackur–Tetrode equation
The Sackur–Tetrode equation is a fundamental formula in statistical mechanics that gives the absolute entropy of an ideal monatomic gas in terms of its volume, temperature, and particle number.
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D.
ideal gas law
The ideal gas law is a fundamental equation in thermodynamics that relates the pressure, volume, temperature, and amount of an idealized gas, providing a simple model for gas behavior under many conditions.
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E.
Gibbs–Duhem equation
The Gibbs–Duhem equation is a fundamental thermodynamic relation that links changes in chemical potential, temperature, and pressure for multicomponent systems, ensuring consistency among intensive variables.
- F. None of above. chosen
- G. Unsure - the case is ambiguous/there is not enough information to decide.
NED2
Entity disambiguation (via description)
gpt-5-mini-2025-08-07
Target entity: van der Waals equation of state Target entity description: The van der Waals equation of state is a thermodynamic equation that improves on the ideal gas law by accounting for the finite size of molecules and the intermolecular forces between them.
-
A.
Ornstein–Zernike equation
The Ornstein–Zernike equation is a fundamental relation in statistical mechanics that links the total and direct correlation functions of a fluid, forming the basis for many liquid-state theories and approximations.
-
B.
Clausius–Clapeyron relation
The Clausius–Clapeyron relation is a fundamental thermodynamic equation that describes how the pressure and temperature of a phase transition, such as boiling or condensation, are related.
-
C.
Sackur–Tetrode equation
The Sackur–Tetrode equation is a fundamental formula in statistical mechanics that gives the absolute entropy of an ideal monatomic gas in terms of its volume, temperature, and particle number.
-
D.
ideal gas law
The ideal gas law is a fundamental equation in thermodynamics that relates the pressure, volume, temperature, and amount of an idealized gas, providing a simple model for gas behavior under many conditions.
-
E.
Gibbs–Duhem equation
The Gibbs–Duhem equation is a fundamental thermodynamic relation that links changes in chemical potential, temperature, and pressure for multicomponent systems, ensuring consistency among intensive variables.
- F. None of above. chosen
Statements (48)
| Predicate | Object |
|---|---|
| instanceOf |
equation of state
ⓘ
real gas model ⓘ thermodynamic model ⓘ |
| accountsFor |
finite molecular size
ⓘ
intermolecular forces ⓘ |
| applicableTo | real gases ⓘ |
| associatedWith | van der Waals forces NERFINISHED ⓘ |
| assumes |
hard-core repulsion modeled by excluded volume
ⓘ
pairwise additive intermolecular attractions ⓘ |
| category | equations named after people ⓘ |
| contributedTo | award of the 1910 Nobel Prize in Physics to van der Waals ⓘ |
| field |
chemical engineering
ⓘ
physical chemistry ⓘ statistical mechanics ⓘ thermodynamics ⓘ |
| hasDimensionlessForm | reduced van der Waals equation NERFINISHED ⓘ |
| hasLimitation |
assumes spherical molecules
ⓘ
limited accuracy at high pressures ⓘ quantitative inaccuracy near phase transitions ⓘ |
| hasVariable |
amount of substance
ⓘ
molar volume ⓘ pressure ⓘ temperature ⓘ |
| historicalSignificance | first simple equation of state to incorporate molecular size and attractions ⓘ |
| improvesOn | ideal gas law NERFINISHED ⓘ |
| includesParameter |
a
ⓘ
b ⓘ |
| inspired |
Peng–Robinson equation of state
NERFINISHED
ⓘ
Redlich–Kwong equation of state ⓘ Soave–Redlich–Kwong equation of state NERFINISHED ⓘ |
| introducedBy | Johannes Diderik van der Waals NERFINISHED ⓘ |
| introducedIn | 19th century ⓘ |
| namedAfter | Johannes Diderik van der Waals NERFINISHED ⓘ |
| parameterRepresents |
a; measure of attractive intermolecular forces
ⓘ
b; effective excluded volume per mole ⓘ |
| predicts |
critical point
ⓘ
liquid–vapor coexistence qualitatively ⓘ non-ideal pressure–volume–temperature behavior ⓘ |
| reducesTo | ideal gas law at low pressure and high temperature ⓘ |
| relatedTo | cubic equations of state ⓘ |
| supportsConcept | law of corresponding states ⓘ |
| symbolicForm |
(P + a(n/V)^2)(V - nb) = nRT
ⓘ
(P + a/V_m^2)(V_m - b) = RT ⓘ |
| usedFor |
estimating critical constants
ⓘ
teaching basic concepts of real gas behavior ⓘ |
| usedIn |
critical phenomena studies
ⓘ
introductory thermodynamics textbooks ⓘ phase diagram analysis ⓘ |
How these facts were elicited
The pipeline generated the facts above by prompting gpt-5.1 with this entity's name + description and the instruction below.
Instruction
You are a knowledge base construction expert. Given a subject entity and a description of it, return factual statements that you know for the subject as a JSON list of dictionaries(triples), where keys must be "subject", "predicate" and "object". The number of facts may be very high, between 25 to 50 or more, for very popular subjects. For less popular subjects, the number of facts can be very low, like 5 or 10. # Requirements - If you don't know the subject at all, return an empty list. - If the subject is not a named entity, return an empty list. - Include at least one triple where predicate is "instanceOf". - Do not get too wordy. - Separate several objects into multiple triples with one object.
Input
Subject: van der Waals equation of state Description of subject: The van der Waals equation of state is a thermodynamic equation that improves on the ideal gas law by accounting for the finite size of molecules and the intermolecular forces between them.
Referenced by (1)
Full triples — surface form annotated when it differs from this entity's canonical label.