THERMAL PROPERTIES OP AMMOIflA 



Experimental Data. - Ex|x-tim. m, on the properties of ammonia 

 are by no means as complete or as concordant as the experiments on 

 water vapor. Hence any formulation for ammonia must be regarded as 

 m. t. !\ trni. it i\< .uui subject to revision as further experimental evidence 

 becomes availall< . 



Ex|H-rinu-nts on the pressure- ten ip -r.it ure relation for saturated am- 

 monia vapor have been made by Regnault. i araday, Bliimcki-, Brill. 

 and Davies.* 



Data on the specific volume of liquid ammonia arc- furnished by the 



experimrnt- nge, D'An :ii<l I)iftrri i, and on the specific 



volume of the saturated vapor l>\ tin i \ixriments of Di The 



iui. nt- <>t ivrman, Guye, and Leduc furnish a few isolated values 



he \olunK- of the superheatnl \.ijx>r. 



Measurement^ of the latent heat of \ ajH.ri/ation have been made by 

 Regnault, Franklin and Kraus, Von Strombeck, Estreicher and Schnerr, 

 I )i-nt . .11 and Jacobus. The values obtained are very discordant. 



Fairly iru>t worthy values of the heat content of liquid ammonia 

 throughout the range 5O-i6o F. are given by the experiments of Die- 



i and I >r Aves. 



Finally, a !" -w \ alues of the specific heat of superheated ammonia are 

 Kivi-n by Keutel, Voller, Wiedemann, Regnault, and Nernst. 



Pressure-Temperature Relation. -The law of Ramsay and Young 

 affords the mo- actory method of calculating corresponding tem- 



peratures and pressures of saturated ammonia vapor. This law is ex- 

 pressed by the equation 



in wliirh R and R' denote the ratio of the saturat x-ratures of two 



in substances at two different pressures, and T, Fdenote the abso- 

 lute temperatures of one of the vapors corresponding respectively to the 

 pressures. Let water and ammonia be the two substances and let T 9 and 

 r. denote respectively the absolute temperatures of saturated steam and 

 ammonia at the same pressure; then the law is fxpffjwd by the simple 

 equation 



For an exhaustive bibliography of the iavwttptioat of ammook, m BaOetia No. 66, 

 University of Illinois Experiment Sutioo. pp. 92-94. 



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