University Physics III · Temperature and Kinetic Theory · 6.09
Real gases and the limits of the ideal model
The compressibility factor pV over nRT as a measure of departure, van der Waals corrections for molecular volume and attraction, isotherms near the critical point, and the condensation an ideal gas can never perform; van der Waals recovers the ideal gas exactly at low density but is a two-parameter interpolation elsewhere, predicting a critical compressibility of three-eighths against a measured value near three-tenths.
Course-map guide · not a complete lesson or simulationScope & orientation
What this subsection covers
The compressibility factor pV over nRT as a measure of departure, van der Waals corrections for molecular volume and attraction, isotherms near the critical point, and the condensation an ideal gas can never perform; van der Waals recovers the ideal gas exactly at low density but is a two-parameter…A strong response uses p-v and p-t state diagrams and states where the model stops being reliable.
Reasoning checklist
Evidence, assumptions and limits
Assumptions to state
State the system, observable, approximation, and conditions held fixed before using a model.
Evidence to collect
What absolute-zero intercept and uncertainty do constant-volume pressure-temperature data support?
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What absolute-zero intercept and uncertainty do constant-volume pressure-temperature data support? Useful evidence includes pressure-temperature pairs, a linear fit with residuals, the extrapolated intercept, propagated uncertainty, and a dead-volume systematic check.
Limits to state
This GioPhysics course map is an adaptable learning sequence, not academic credit, accreditation, or a universal university syllabus.
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This GioPhysics course map is an adaptable learning sequence, not academic credit, accreditation, or a universal university syllabus. Third-semester content is the least standardised of the introductory sequence: departments place oscillations, waves, optics, and thermal physics differently, and the modern-physics units here are a bounded survey rather than a complete course in relativity, quantum mechanics, atomic, nuclear, or particle physics. Follow your institution's published scope, notation, laboratory programme, and assessment rules. A result should be checked against units, signs, limiting cases, and the conditions under which its model was derived.
Diagram & examples
Work the claim before choosing an equation
Interactive concept map
Follow the model from claim to evidence.
Model, evidence, and boundary
When should a model used for Real gases and the limits of the ideal model be revised?
modelModel, evidence, and boundary turns the stated idea into a representation that can make a prediction.
Example questions
Try the reasoning before revealing the structure.
When should a model used for Real gases and the limits of the ideal model be revised?
Quick check
Test the reasoning, not recall
When should a model used for Real gases and the limits of the ideal model be revised?
Choose an answer to test the model.