Chemistry / Unit 7 Chem 1249 short lesson, about 20 seconds
Standard Temperature and Pressure: the 1 atm Convention
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The idea
Standard temperature and pressure, STP, historically fixed pressure at exactly 1 atmosphere and temperature at 273.15 kelvin, the convention most pre-1982 chemistry literature still uses.
In practice
Under this convention, one mole of an ideal gas occupies about 22.4 liters at STP.
Where people slip
This 1-atm convention is not obsolete fiction — much still-cited data, and this course's own earlier units, use it by default.
Your place on the trail
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