( 552 ) 



pvA = .1.1 + ^^ (3) 



'M 



we }nit r^i=l, we oblaiii: 



1 + ((j, . 20.13 = Aa + Ba . 

 if (t^, is Ihe c*on'CS|»()ii(li]ig coenicieiit ot" prossiiix' \ariali(tii. 



From llic l\\(i relations between .1^ and 7i.i,.ljniav lic dcrlNcd 

 and tlion .j^f,, may be tbnnd from the relation^): 



.4,1 =r .1.1,, (1 -f 0.()U3G(525 /) (4) 



A diffienby arises from the imcerlaiiily of ((/, for llic mixtures: 

 an erroi' in (tj, passes over into .l.i„ "20 limes maünilicd. I'his may 

 lie avoided in the following- manner: 



As normal temperatnre \\(' sliaU tem|»oraiily adopt '20^ ('., and 

 tiieii we write KA.MKKi,iN(in O.nnks' cqiialion for the ai-ea of the 

 jtressnres eonsidered iiere: 



V is the volume i-eally occupied l»y the gas, ]"v.,^ the normal 

 volume at 20° C, wa. the xobime occupied l»y the (juantity of gas 

 considered at 20" C and 1 atmosphere. 



Now : 



I 0.003(5025 ) 



Ak — A/, ) 1 H (/- 20) 



A,„ I ^ 1 _p 20 X 0.003GG25 j 



= .4a-.,„ 1 4 n.()()34125 (/— 20) (0) 



A ('(unparison with 



I BaV.x) 

 I' »^= ^\\ J'U -r — -^T-j (7) 



where I'v i-' 'he noi-mal volunu' at 0^ C, gi\es the relations: 



Aa . r.v = ^U . TX„ 



/>.i. vi = Bk. v\. <^> 



w hence : 



-'•;." -n, '■" 



Hence it is given that for ihe mixture O!) at 20 .13C'. : 



Bk 



= — U. 003403. 



From (5) follows, putting /- 2(P.13 and r= Tv.,,: 

 1) Comp. Comm. N . 71, These Proc. lil June '2\). lUOl, p. 130. 



