Symbol indicating that a gas volume has been expressed as if it were at standard temperature (0°C), standard pressure (760 mm Hg absolute), dry; under these conditions a mole of gas occupies 22.4 liters. ... (05 Mar 2000) ... 
standard temperature and pressure, dry; denoting a volume of dry gas at 0° C and a pressure of 760 mm Hg.
Type: Symbol Definitions: 1. Abbreviation indicating that a gas volume has been expressed as if it were at standard temperature (0°C), standard pressure (760 mm Hg absolute), and dry; under these conditions a mole of gas occupies 22.4 L.
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