Abstract
A new analytical technique was developed previously for the photometric determination of a trace of iron in water and in high-purity aluminum with sodium sulfide in alkaline media by the present authors. In the previous paper, hydrazin sulfate was used as the reducing reagent for iron (III), but no experiment was carried out by using other reducing reagents. The present paper describes the experiments carried out by using various reducing reagents, i.e. ascorbic acid, sodium hydrogen sulfite, hydroxylamine hydrochloride and hydrazine sulfate. The results showed that the use of 2 ml of 5% hydroxylamine hydrochloride gave the best results for the determination of iron in water because of the highest stability of the color and the sensitivity, and that the use of 2 ml of 0.5%hydrazine sulfate described in the previous paper or 3 ml of 5% sodium hydrogen sulfite was better than other reducing reagents for the determination of iron in aluminum. Analytical results of well and city waters obtained by the recomended procedure using hydroxyl-amine hydrochloride and those by the ο-phenanthroline method are also described.