ABSTRACT

(p,p,T) measurements and visual observations of the meniscus for ammonia were carried out carefully in the critical region over the range of temperatures: ?1 K 6 (T ? Tc) 6 0.04 K, and of densities: ?19 kgAem?3 6 (q ? qc) 6 19 kgAem?3 by a metal-bellows volumometer with an optical cell. Vapor pressures were also measured at T = (310, 350, and 400) K. The critical parameters of Tc and qc were determined based on the results of observation of the critical opalescence. The critical pressure pc was determined from the present measurements at Tc on the vapor pressure curve. Comparisons of the critical parameters with values given in the literature are presented.

Compounds

#	Formula	Name
1	H3N	ammonia

Datasets

The table above is generated from the ThermoML associated json file (link above). POMD and RXND refer to PureOrMixture and Reaction Datasets. The compound numbers are included in properties, variables, and phases, if specificied; the numbers refer to the table of compounds on the left.
Type	Compound-#	Property	Variable	Phase	Method	#Points
POMD	1	Critical temperature, K ; Liquid		Liquid Gas	Visual observation in an unstirred cell	1
POMD	1	Critical density, kg/m3 ; Liquid		Liquid Gas	metal-bellows volumometer	1
POMD	1	Vapor or sublimation pressure, kPa ; Liquid	Temperature, K; Liquid	Liquid Gas	Closed cell (Static) method	18
POMD	1	Vapor or sublimation pressure, kPa ; Liquid	Temperature, K; Liquid	Liquid Gas	Closed cell (Static) method	18
POMD	1	Mass density, kg/m3 ; Fluid (supercritical or subcritical phases)	Temperature, K; Fluid (supercritical or subcritical phases) Pressure, kPa; Fluid (supercritical or subcritical phases)	Fluid (supercritical or subcritical phases)	ISOCHOR	26

Thermodynamics Research Center / ThermoML | Journal of Chemical Thermodynamics

Critical parameters for ammonia

Sato, M., Masui, G., Uematsu, M.

ABSTRACT