( 377 ) 



Physics. — ''Tlui niluUtii of the hur of correspon.dinr/ daks for 

 uilvtiurs of nicthf/I chloride and carbon dio,r.ide" ^y Proi'. 

 H. KAMKKLiN(iH Onnes and Dr. C. Zakrzkwski. (Communication 

 W. 92 from the Physical Laboratory at Leiden by Prof. 

 Dr. H. Kamerlingh Onnes) (Continued). 



(Coiiiniiuiicaled in the meeling of October 29, rJOi). 



§ 5. Further approxlmatLons. By second approximation we get 

 by takina- also 7>' into consideration: 



1 



i>, i\ 



1 



)., V, 



1 = — (^, - p,) - ^ (/>! - />.) {l\ + 2/>,). 



(2) 



If, however, we take ]P into consideration, it is more rational to 

 do the same with C, and we have: 



B B' A . f . G^\ 



I 



Vx ^'l 



A' 



1 =4^ (i> -P.) - ^ (P -1^) 1 i^ + ( 1 - f.) ^P^ + P^Y^^ 



CA 



According to the reduced equation of state -^ is about '/, for 



methyl chloride at 20''. 



The repetition of the calculations of § 2 yields : 



TABLE III Second virial coefficients of mixtures of carbon dioxide 

 {X = 0) and methyl chloride {fv = 1) to the 2"^ and S'-^^ approximations. 



The repetition of the calculalions of § 3 and § 4 with these 

 corrected values gives: 



1) Here are two delerminations of Keesom agreeing willi 1 and II and I and III, 

 calculated according to (2) and (3) (data see Goinm. W. 88j. 



