Engineering English
Fugacity
Chemical Engineering · Last updated: July 30, 2026 · How this entry was written
Definition: Fugacity is a thermodynamic property that represents the tendency of a substance to escape or leave a phase. It corrects for non-ideality in phase equilibrium calculations.
Example in context
“The fugacity coefficient approach corrects the ideal gas law for real gas behavior in the compressor design.”
“Fugasite katsayısı yaklaşımı, kompresör tasarımında ideal gaz yasasını gerçek gaz davranışı için düzeltir.”
Where engineers use it
Fugacity is used in equations of state to model high-pressure phase behavior. Engineers compute fugacity for vapor-liquid equilibrium in natural gas processing, refinery separators, and supercritical extraction.
Practice: can you use “Fugacity” at work?
You are designing a high-pressure separator for natural gas liquids. Use the Peng-Robinson equation of state to compute the fugacity of methane in the vapor and liquid phases to check for equilibrium.
Show a model answer
“Compare the fugacity of the vapor with the liquid to verify phase equilibrium.”
“Fugacity” in 21 languages
| English | Fugacity |
|---|---|
| Turkish | fugasite |
| French | fugacité |
| German | Fugazität |
| Spanish | fugacidad |
| Chinese | 逸度 |
| Arabic | الفراطية |
| Portuguese | fugacidade |
| Russian | фугитивность |
| Japanese | フガシティー |
| Italian | fugacità |
| Vietnamese | nhiệt động lực thoát |
| Hindi | फुगैसिटी |
| Thai | ฟูกาซิตี |
| Indonesian | fugacity |
| Korean | 퓨가시티 |
| Bengali | ফুগাসিটি |
| Dutch | fugaciteit |
| Swedish | fugacitet |
| Finnish | fugacity |
| Ukrainian | фугітивність |
Frequently asked questions
What does Fugacity mean in engineering?
Fugacity is a thermodynamic property that represents the tendency of a substance to escape or leave a phase. It corrects for non-ideality in phase equilibrium calculations. In Chemical Engineering, the term carries a usage-frequency rating of 10/10 in the Engineering English library.
How do you pronounce Fugacity?
Fugacity is pronounced /fjuːˈɡæsɪti/ (IPA). The Engineering English app plays audio for the term and checks your pronunciation with speech recognition.
How is Fugacity used in a sentence?
Example from an engineering context: “The fugacity coefficient approach corrects the ideal gas law for real gas behavior in the compressor design.”
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