﻿Ideal Rep 'activities of Gases. 



VA 



values, however, still require correction for the deviation 

 from the ideal state shown at normal temperature and pressure 

 by the gas. We would nevertheless urge that in future 

 investigations greater attention be paid to the deviations of 

 the gases from the ideal state within the previously referred 

 to pressure-changes. It is obvious from equation (13) that 

 for any number of gases [1], [2], [3], . . . &c. 



iMu-1 : 2/^o-l : s/^o—1 • 



= 0i(i/a — 1) : </>2(2^ — 1) : &j(3/*— 1) • • • • 



.... (14) 



where (,/xq — 1), G^o - 1)« • • • & c - represent the ideal re- 

 fractivities, corrected for the deviations of the gases from 

 Avogadro's hypothesis, expressed in terms of the refrac- 

 tivities of the gases at normal temperature and pressure and 

 of the critical constants of the several gases. 



In Table I. are given the mean uncorrected values of the 

 refractivities at normal temperature and pressure for the 

 several wave-lengths indicated, duly weighted after con- 

 sideration of the original memoirs, the values of </> ; and the 

 corrected ideal refractivities (/u — 1). 



Table I. 



Gas. 



Hydrogen 



Aii- 



Oxygen 



Nitrogen 



Argon 



Refractivity 

 Wave-length at 0° C. and 

 in mm. XlO u . 760 mm. Hg. 



(m-1)10 7 . 



436 

 486 

 578 

 589 

 656 

 436 

 486 

 578 

 589 

 656 

 436 

 486 

 578 

 589 

 656 

 436 

 486 

 578 

 589 

 656 

 436 

 486 

 578 

 644 



1412 

 1406 

 1391 

 1392 

 1387 

 2965 

 2948 

 2927 

 2926 

 2916 

 2747 

 2735 

 2706 

 2711 

 2697 

 3020 

 3012 

 2976 

 2976 

 2982 

 2S51 

 2838 

 2803 

 2796 



1-00051 

 1-00051 

 1-00051 

 1-00051 

 1-00051 

 0-99964 

 099964 

 99964 

 0-99964 

 0-99964 

 0-99927 

 0-99927 

 0-99927 

 0-99927 

 0-99927 

 0-99972 

 0-99972 

 0-99972 

 0-99972 

 0-99972 

 0-99932 

 0*99932 

 0-99932 

 0-99932 



Ideal 

 Refractivitv 

 (j*o-l)10*.| 



1413 

 1407 

 1392 

 1393 

 1388 

 2964 

 2947 

 2926 

 2925 

 2915 

 2745 

 2733 

 2704 

 2709 

 2695 

 3019 

 3011 

 2975 

 2975 

 298 1 

 2849 

 2836 

 2801 

 279 I 



