408 



It is seen that here the value of tlie term liv is aboni 22° , of 

 the principal term. 



The discrepancies between calcniated and found values — also 

 in the following examples — must be chiefly ascribed, besides to 

 experimental difticulties and small approximations in the derivation 

 of the formula, to the often inaccurately known values of the m^/ca/ 

 pressiires. Even a slif^ht error in them gives already rise to a com- 

 paratively great change in the value of (1 — t)'. 



The following value is immediately found for ^7" according 



to (11): 



^'V, =z 7,, X 1,1 X 0,068 X 0,087 =0,00027. 

 The value 0,05:100 = 0,00050 was found (see Table 21 on 

 p. 160—161 and p. 175 in Kr.) '). 



2. Metaxylene-Benzene. There we have what follows. 



This gives: 

 10= V,Xl,2X562(0,0185^-7, 1,05. 0,136 j0,220 -7J,2 . 0,136 . 1,608|) 



= 2351 (0,0185 + 0,0239 \ 0,220—0,065 j) 



= 2351 (0,0185 I 0,0037) = 2351 >; 0,0222 = 52,2 gr. cal. 



Kkkmann found 57 gr. cal. The agreement is again very satis- 

 factory (taking the above remarks into consideration). The term 

 with tiv is 20Vo of the principal term. Further: 



^7, = 7,^ X 1,2 X 0,136 X 0,155 = 0,00105. 



Kr. found 0,15:100 = 0,00150. The order of magnitude is the 

 same in every case. * 



The mixtures with CCl^ as component all present deviations. Now 

 CCI4 is certainly associated (see also Kk., p. 68 and 140), so that 

 this accounts for the deviations. 



^) It is not very clear in Kremann's records whether we should divide by 100, 

 or by 1/2 (^'i" + ^2°) = 195,5. (Gf. p. 175). In the latter case A^r would be 

 = 0,00026, in perfect agreement with the calculated value. As regards Young's 

 value, it deviates considerably from that of Kremann. He found viz. 0,16o/o instead 

 of 0,05 %, hence more than 3 limes the value. Also for to there are often large 

 differences. 



