| 摘要 |
PURPOSE:To make possible the easy quantitative determination of iron in water by ionizing and dissolving the insoluble iron in the water by an ionizing agent then bringing the dissolved iron of which the ion value is made uniform by an oxidizing agent or reducing agent into reaction with the resultant produce in the co-existence of a dye. CONSTITUTION:The insoluble iron in the test water is ionized by using, for example, oxalic acid as the ionizing agent and is thereafter unified to bivalent iron ion by using, for example, ascorbic acid as the reducing agent. The color former consisting of, for example, sodium p-phenanthroline disulfonate is added to the dissolved iron to form a color, then a dye consisting of, for example, 'brilliant blue FCF(R)' is added thereto. The color forming condition thereof is observed with the naked eyes as a change in the color tone in the co-existence of the dye, by which the concn. of the iron ion in the test water is quantitatively determined. The easy quantitative determination of the very slight iron in the water with high accuracy is thus made possible without using analyzing apparatus. |
