**2.2.4 Interference studies**

The interference effects of many cations and anions on the determination of 5 g L-1 iron (II) were examined. The results summarized in Table 1.


Table 1. Effect of foreign ions on the determination of 5 μg L-1 of iron (II) in solution

In the table, the tolerable concentration of each diverse ion was taken as a highest concentration causing an error of ± 3 %. Most of the ions examined did not interfere with the determination of iron (II). The major interference was iron (III) at the amounts of 200 g L-1. It is apparent from the Table 1 that the proposed method can tolerate all of the interfering species tested in satisfactory amounts and it is therefore adequately selective for the determination of Fe (II) and total iron.
