model comparisons

Comparing Fundamental Constants

The following table compares the various fundamental constants used by the different formulations:

Property	IAPWS-95	IAPWS-IF97	NBS/NRC-84	IFC-67
Molecular weight, kg/kmol	18.01526800	18.01525808	18.01528000	18.01534000
Triple point temperature, ºC	0.01	0.01	0.01	0.01
Triple point pressure, bar	0.00611657	0.00611657	0.006117313	0.006112444
Critical point temperature, ºC	373.946	373.946	373.976	374.150
Critical point pressure, bar	220.64	220.64	220.55	221.20
Critical point density, kg/m3	322.00	322.00	321.89	315.46