( 42 ) 

 B—P—pV—y 



V 



(B) 



As for the concentration of dissolved iirecipitate in the third place, 

 this must be expressed bj 





(4) 



So the equation (1) becomes : 



A—P—pV—2.y B—P—pV~y_ pV 

 V V ' V 



or 



(A— P— pV— 2y) (B— P— pV— y) = k, pV\ . . (5) 



Now one more equation, expressing the reaction according to 

 which precipitate combines with precipitinogen substance. This is 

 to be written down as follows. 



Concentration free precipitinogen substance X concentr. dissolved precipitate 

 = ko concentr. compound precipitinogen subst. — precipitate. 



A-P--pV-2y pj[_ y_ 



or 



(A— P— pV— 2y) p = k, y (6) 



By putting shortly P-j-pF=i^' and by substituting the value of 

 y of equation (6) into equation (5) we obtain 



(a-P^-2p — -^ (b-P'-p ^^^ = K ?V" 



(7) 



In this equation are known : 



1st. j\^ the total quantity of precipitinogen substance (diluted 

 horseserum added) ; 



2"'^. B, tlie total quantity of precipitin (calfserum) used ; 



3'd. V, the volume of the liquid resulting from the mixing of 

 the two components ; 



4*^. P, the quantity of solid precipitate directly observed. 



unknown are : 



1st. 2?, the quantity in percentages of precipitate which is dissolved 

 (so 2^ represents the sohibility of the precipitate) ; 



2''^. k^, the constant for reaction of the formation of precipitate; 



3'd, k^, the constant for reaction of the formation of the com- 

 pound precipitate-precipitinogen substance ; 



