standard conditions for gases
Temperature, 273.15 K (0°C) and pressure of 10E5 pascals. IUPAC recommends that the former use of the pressure of 1 atm as standard pressure (equivalent to 1.01325 x 10E5 Pa) should be discontinued.
See: STP
PAC, 1990, 62, 2167. 'Glossary of atmospheric chemistry terms (Recommendations 1990)' on page 2216 (