Density, Temperature, and Pressure of Substances. 335 



C is given by 



[p\ l3 \i-^VJu^i ~ Spy* 



Pi 



The above equation may then be written 

 3 



*P 



vM /3 -pf)=Pi~P2- .... (7) 



We have also 



3 ;V25RT C 



4p l/3- mpfyfr^T) 



, and hence yjr 2 (T) = 



7RT C 



In the case o£ pentane and hexane we obtain for ^ 2 (T) from 

 this equation the values 90 3 and 90G respectively, which 

 agree fairly well with 91*7 and 85'8, the mean values of 

 f 2 { T) obtained from Table V. 



The mean value of ~ for each substance is given at the 



\j 



bottom of Table YI. The agreement with the corresponding 



4 



values of T p l J z is fairly good. But it will be noticed that 



equation (7) does not on the whole agree so well with the 

 facts as either equation (1) or (5). 



Table VI. 



Methyl 

 butyrate. 



Heptane. 



Di- 



isobutyl. 



Hexane. 



Hexa- 



methylene. 



Carbon 

 tetrachloride. 



T. 



# 2 (T). 



T. 



un 



T. 



un 



T. 



* 2 (T). 



•857 

 •849 

 •845 

 •837 

 •831 

 •826 

 •823 

 •820 

 •818 

 •820 , 



T. 



* 2 (T). 



T. 



un 



383 

 403 

 423 

 443 

 463 

 483 

 503 

 523 

 543 

 551 



•930 

 •923 

 •916 

 •909 

 •903 

 •898 

 •894 

 •890 

 •890 

 •888 



273 

 353 

 373 

 383 

 393 

 413 

 433 

 453 

 473 



•694 

 •702 

 •707 

 •707 

 •705 

 •701 

 •698 

 •677 

 •662 



363 

 383 

 403 

 423 

 443 

 463 

 483 

 503 

 523 

 543 



•861 



•855 

 •848 

 •843 

 •836 

 •832 

 •827 

 •823 

 •822 

 •822 



333 

 353 

 373 

 393 

 413 

 433 

 453 

 473 

 493 

 503 



363 

 383 

 403 

 423 

 443 

 463 

 483 

 503 

 523 

 543 



•897 

 •890 

 •884 

 •876 

 •874 

 •869 

 •866 

 •863 

 •861 

 •862 



273 

 373 

 393 

 413 

 433 

 453 

 473 

 493 

 513 

 533 



1-18 

 114 

 113 

 1-12 

 111 

 111 

 1-10 

 1-10 

 1-09 

 1-13 



Mean 



•924 





•695 





•837 





•833 





•874 





112 



i* 



•884 





•822 





•825 





•822 





•860 





138 



