Molar volume of ideal gas (273.15 K, 100 kPa)
Physico-chemicalExact
= 22.710 954 64… × 10−3 m3 mol−1
- Value
- 22.710 954 64… × 10−3 m3 mol−1
- Standard uncertainty
- exact
- Relative uncertainty
- exact
- Status
- Exact since the 2019 SI redefinition
- Symbol
- Source
- CODATA 2022 via NIST · NIST entry
NIST prints this exact value cut to 10 digits. ConstantID recomputes it from the defining constants: 0.022 710 954 641 485 575 06…
Use in a calculation
# molar volume of ideal gas (273.15 K, 100 kPa), CODATA 2022 (NIST)
molar_volume_of_ideal_gas_273_15_k_100_k = 2.271095464148557506e-2 # m^3 mol^-1, exact
# SciPy: scipy.constants.physical_constants['molar volume of ideal gas (273.15 K, 100 kPa)']What it is
The volume one mole of an ideal gas occupies at 0 °C and 100 kPa (1 bar), about 22.71 litres.
It is built only from constants that have exact values since 20 May 2019, so it is exact too; CODATA 2018 was the first adjustment to list it that way.
How the value changed, 1998–2022
Each point is one CODATA adjustment, plotted as its difference from the 2022 value; the bars show one standard uncertainty (an arrowhead means the bar runs off the chart). Diamonds mark adjustments in which the value was exact.
Relative uncertainty
| CODATA | Value (uncertainty) | Relative uncertainty | Change from previous |
|---|---|---|---|
| 2022 | 22.710 954 64… × 10−3 | exact | exact |
| 2018 | 22.710 954 64… × 10−3 | exact | +0.6 σ of 2014 |
| 2014 | 22.710 947(13) × 10−3 | 5.7 × 10−7 | −0.3 σ of 2010 |
| 2010 | 22.710 953(21) × 10−3 | 9.2 × 10−7 | −0.7 σ of 2006 |
| 2006 | 22.710 981(40) × 10−3 | 1.8 × 10−6 | +0.0 σ of 2002 |
| 2002 | 22.710 981(40) × 10−3 | 1.8 × 10−6 | +0.0 σ of 1998 |
| 1998 | 22.710 981(40) × 10−3 | 1.8 × 10−6 |
“Change from previous” is the shift in the value divided by the standard uncertainty of the previous adjustment. Earlier values are converted into the current unit where NIST changed it (for example J s to J Hz⁻¹).