text: It is as important to indicate the applicable reference conditions of temperature and pressure when stating the molar volume of a gas as it is when expressing a gas volume or volumetric flow rate. Stating the molar volume of a gas without indicating the reference conditions of temperature and pressure has very little meaning and can cause confusion.
  The molar volume of gases around STP and at atmospheric pressure can be calculated with an accuracy that is usually sufficient by using the ideal gas law. The molar volume of any ideal gas may be calculated at various standard reference conditions as shown below:
  * V = 8.3145 × 273.15 / 101.325 = 22.414 dm/mol at 0 °C and 101.325 kPa
  * V = 8.3145 × 273.15 / 100.000 = 22.711 dm/mol at 0 °C and 100 kPa
  * V = 8.3145 × 288.15 / 101.325 = 23.645 dm/mol at 15 °C and 101.325 kPa
  * V = 8.3145 × 298.15 / 101.325 = 24.466 dm/mol at 25 °C and 101.325 kPa
  * V = 8.3145 × 298.15 / 100.000 = 24.790 dm/mol at 25 °C and 100 kPa
  * V = 10.7316 × 519.67 / 14.696 = 379.48 ft/lbmol at 60 °F and 14.696 psi (or about 0.8366 ft/gram mole)
  * V = 10.7316 × 519.67 / 14.730 = 378.61 ft/lbmol at 60 °F and 14.73 psi
  Technical literature can be confusing because many authors fail to explain whether they are using the ideal gas constant R, or the specific gas constant R. The relationship between the two constants is R = R / m, where m is the molecular mass of the gas.
  The US Standard Atmosphere (USSA) uses 8.31432 m·Pa/(mol·K) as the value of R. However, the USSA in 1976 does recognize that this value is not consistent with the values of the Avogadro constant and the Boltzmann constant.