some Thermodynamical Relations. 



45 



It will be seen that the temperatures of oxygen recalculated 

 from those of sulphur, when c — —'0001652, agree remark- 

 ably well with the mean of the temperatures recalculated from 

 the ratios with water and alcohol. 



Temperatures of 



17. Acetic Acid and Water. 



H 9 0. 



water taken as correct. For liquid acetic acid c = '0003186 ; 

 for solid acetic acid c = — -000852. 



In the ' Philosophical Transactions,' Part 2> 1884, it was 

 shown experimentally by Ramsay and Young that the vapour- 

 pressures of solid acetic acid were lower than those of the 

 liquid acid at the same temperature, and curves were con- 

 structed showing the relation of temperature to pressure for 

 both the solid and the liquid acid. The absolute temperatures 

 corresponding to definite pressures were read from these curves. 

 For pressures below 5 millim. the vapour-pressures of water 

 adopted by Regnault were not employed, the values calculated 

 from his empirical formula representing the relation of tem- 

 perature to pressure of water between 0° and 100° being pro- 

 bably more correct. 



a. Liquid Acetic Acid and Water. 





Eatios. 



Absolute temperatures 



Pressures. 



of Acetic Acid. 



From observed 



Smoothed. 



Recalculated. 



Observed. 





temperatures. 









millim. 







o 



o 



5 



10175 



1-0188 



279-35 



27901 



6 



10193 



1-0195 



282-2 



28214 



7 



1-0202 



10202 



284-6 



284-64 



8 



10212 



1-0209 



286-8 



286-91 



9 



10219 



1-0215 



288-8 



288-88 



10 



1-0222 



1-0220 



290-55 



290-6 



50 



1-0311 



1-0305 



320-8 



321-0 



100 



1-0345 



10347 



336-0 



335-9 



150 



10369 



10375 



3456 



345-4 



200 



1-0392 



1-0395 



3530 



352-9 



300 



1-0426 



10424 



363-7 



363-75 



400 



1-0447 



10447 



3719 



371-9 



500 



1-0455 



1-0465 



378-5 



378-15 



600 



10478 



1-0480 



384-1 



384-0 



700 



10506 



1-0495 



38905 



389-45 



b. Solid Acetic Acid and Water. 



2 



10423 



1-0422 



2729 



272-89 



3 



1-0372 



1-0374 



27715 



27710- : 



4 



1-0335 



10335 



280-15 



280-14 



5 



1-0306 



1-0307 



282-6 



282-60 



6 



1-0284 



1-0284 



284-7 



284-67 



7 



10264 



1-0261 



286-3 



286-37 



8 



1-0244 



10244 



287-8 



287-8 



9 



1-0226 



1-0226 



289-1 



28908 



