the procedures, aliquots of standard iron, lead, and arsenic solutions were added to one of the samples previously analyzed and the synthetic mixtures carried through the procedures. Recoveries were good (Table 11). ACKNOWLEDGMENTThe authors thank Samuel Sitelman for his suggestions, and Leonard Markowitz for his preliminary experimental work on the colorimetric method for iron.

No abstract

o-phenanthroline) is to be used or 10 to 60 of iron if 4,7-diphenyi-l,10phenanthroiine (bathophenanthroline) is to be used. Dissolve the sample in 10 ml. of 8.0.V hydrochloric acid in h small beaker, transfer this solution to a 125-ml. separatory funnel, and complete

No abstract

No abstract