Oct. 14, 1918 



Chemistry of Sweet-Clover Silage 



119 



the true neutral point; Ph8.3, the point of color change for phenolph- 

 thalein; and Ph9-3> the point of color change for thymolphthalein. The 

 N/20 sodium hydroxid was added until equilibrium was reached for 

 each point and the total cc's noted. When the last point was reached, 

 25 cc. of formaldehyde solution which had previously been neutralized 

 to a hydrogen-ion concentration of Ph9.3 was added and N/20 sodium 

 hydroxid added again until the potential indicated a concentration of 

 Ph9-3- This last operation gave the figures for calculating the titrable 

 nitrogen. 



The number of cubic centimeters of N/20 sodium hydroxid necessary 

 to titrate to the true neutral point, Ph7, also to the color change of 

 phenolphthalein Ph8.3, and to the color change of thymolphthalein, 

 Ph 9.3 are given in Table IV. 



Tabi,E IV. — Quantity, in cubic centimeters, of N/20 sodium hydroxid necessary to titrate 

 to three different hydrogen-ion concentrations, Ph 7 Pn 8-3, and Ph 9-3 



[Each sample represents the extract from s gm. of silage] 



TITRATION TO Ph7 



Age of silage. 



Alfalfa alone. 



Alcohol. 



Sweet clover alone. 



Water. Alcohol. 



Sweet clover and corn- 

 chop. 



Alcohol. 



Days. 

 o 



I 



2 



3 



4 



6 



7 



8 



10 



13 



15 



17 



21 



29 



43 



64 



2-3 



6.0 



6.3 

 6. I 

 4.8 



5-7 

 9.6 

 8. I 

 9.4 



10. o 

 12. o 



11. 6 



13- I 

 16. o 

 19. o 



19.4 



22. O 



4.2 



5-3 

 7-5 

 7.8 



7-9 

 7-5 

 7.6 

 9.6 



10. 4 



11. I 



12. o 

 13.0 

 14. 2 

 17.0 

 21.3 

 22. 6 

 24. 7 



2.7 

 3-6 

 4. 6 



6.9 

 10.3 



7.0 



10. 2 



9.8 



8.6 



10. 6 



11. 8 



II- 5 

 10. o 



IO-5 

 10. I 



1.9 

 2.6 



3-9 

 5-2 

 6.0 



5-4 



5-7 

 8-3 

 8.6 

 9.0 



10. 6 

 10.8 



11. 2 

 II. 2 

 II. 7 

 13.0 



1.4 

 2.9 

 3-5 

 4.3 

 8.0 

 8.0 



10. 2 

 9.6 



12. o 

 12. I 



11. 7 

 15-2 

 15-0 

 14-7 

 16.5 

 17-3 



2. 2 



2-5 



3-6 

 4. I 

 6.0 

 6.2 



9.6 

 8.4 

 II. I 

 12.5 

 13.0 

 14.9 



15- 1 

 16. 7 



19. o 



20. I 



