helium
- Formula: He
- Molecular weight: 4.002602
- IUPAC Standard InChIKey: SWQJXJOGLNCZEY-UHFFFAOYSA-N
- CAS Registry Number: 7440-59-7
- Chemical structure:
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Phase change data
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Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Data compiled by: Thermodynamics Research Center, NIST Boulder Laboratories, Chris Muzny director
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
Tc | 5.2 | K | N/A | Angus, de Reuck, et al., 1977 | Uncertainty assigned by TRC = 0.0005 K; in terms of a temp. scale related to the 1958 He-4 scale, T-58 by 1.001 T-58 + 0.001 K |
Quantity | Value | Units | Method | Reference | Comment |
Pc | 2.244 | atm | N/A | Angus, de Reuck, et al., 1977 | Uncertainty assigned by TRC = 0.002 atm |
Quantity | Value | Units | Method | Reference | Comment |
ρc | 17.40 | mol/l | N/A | Angus, de Reuck, et al., 1977 | Uncertainty assigned by TRC = 0.01 mol/l |
References
Go To: Top, Phase change data, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Angus, de Reuck, et al., 1977
Angus, S.; de Reuck, K.M.; McCarty, R.D.,
International Thermodynamic Tables of the Fluid State - 4 Helium, Pergamon, New York, 1977. [all data]
Notes
Go To: Top, Phase change data, References
- Symbols used in this document:
Pc Critical pressure Tc Critical temperature ρc Critical density - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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