J. F. Tocher 



.181 



A second set of experiments was carried out in which the ratio 

 mjm^ = 10 instead of 2, that is, in each case 10 times more citric acid 

 than phosphate was used in each separate experiment. The undernoted 

 table (Table IV) shows the quantities used and the results obtained. 

 This set of experiments when plotted against the theoretical curve ex- 

 pressed in equation (1) was found to be a very bad fit. In order to deter- 

 mine the best fitting equation the ratio of the exponent x to the exponent 



c in the general equation C ■ 



l\u'' 



k.M 



- was determined where C, l\ and k^ 



are constants. The ratio — was found to be egixal to 1-0669 



mean 2: 



16/15. 



The following table (Table IV) and accompanying diagrams (Diagrams 3 

 and 4) show the observed results and those reached from the ecpiation, 



C = --j^ , or log C = 1 6 log u — 1 5 log w. 



Table IV. Quantities of mineral phosphate and citric acid constant — 



dilution, varied. 



1 10 grams citric acid 



( 1 gram mineral phosphate 



c.-, 30 

 oO 





20 



£•3 10 





N'uluinc in Cubic Cclitiiiicdcs 



;-S 500 2500 5000 



Diagram 3. See columns 7 and 8, Table IV. 



03 s a 



^ "" o 



111 



COS 

 %^ 



-SO 



54 



/ Volume in Cubic Centiuietres 



500 " 2500 5000 



Diagram 4. See column 6, Table IV. 



