SPECIFIC HEAT OF AMMONIA. 407 



Va The particular specific volume a. 



^6 The particular specific \olume b. 



«'2.6593 The particular specific volume 2.6593 ccs/gm. 



V Total volume enclosed by the container. 



E ■ Average voltage drop across heating coil during a heating period. 



I Average current through heating coil during a heating period. 



M Total mass of ammonia in container. 



Ml Mass of ammonia vapor in container. 



M2 Mass of liquid ammonia in container. 



p Pressure. 



L Total heat of vaporization of the liquid. 



K Modulus in Newton's Law of Cooling, using Centigrade scale. 



k Modulus in Newton's Law of Cooling, using resistance scale. 



R Resistance of thermometer at temperature d. 



Rk Constant in Keyes equation of state. (32) 



i?o Resistance of thermometer corresponding to the temperature 



at beginning of an initial line. 



Ri Resistance of thermometer corresponding to the temperature 



at end of an initial line. 



R2 Resistance of thermometer corresponding to the temperature at 



end of a heating period. 



R3 Resistance of thermometer corresponding to the temperature at 



end of a final line. 



Ra Resistance of thermometer corresponding to da- 



Rm Resistance of thermometer corresponding to dm- 



i?o° Resistance of thermometer at °C. 



i?ioo° Resistance of thermometer at 100 °C. 



bR Change of resistance of thermometer corresponding to bd. 



— - The equivalent on the resistance scale of — -^ 



dt ^ dt 



— - The equivalent on the resistance scale of — ^ 

 dt ^ dt 



^ The equivalent on the resistance scale of (^ + ^) 

 dt \dt dt/ 



t Time. 



to Time at beginning of an initial line. 



ti Time at end of an initial line, 



fe Time at end of a heating period. 

 is Time at end of a final line. 



