418 



Solution Preparation (sec. 1) 



pH M/15 dibasic sodium phosphate M/15 potassium acid phosphate 



Standard Buffer (mcilvaine) (pH 2.2-8.0) 



STOCK solutions: 



0.1 M citric acid (anhydrous): 19.212 gm. made up to 1000 ml. with 



distilled water 

 0.2M disodiiim phosphate: 28.396 gm. made up to 1000 ml. with dis- 

 tilled water 

 For desired pH mix correct amounts as indicated below: 



