Simultaneous Determination of Fe(II) and Fe(HI) by Spectrophotometry with 1,10-PhenanthroIine in Paddy Soil
Qu Dong Wang Baoli(Department of Basle Course) (Central Laboratory)
In HAc-NaAc buffer systcm.two complexes of Fc(Ⅱ ) and Fc(Ⅲ) with 1,10-phcnanthrolinc have an identical absorbancc coefficient at 390.5nm.Thc Fc(Ⅱ ) complex has an absorbancc maximun at 510nm.At this wavelength, there is also a little absorption by Fc(Ⅲ ) complex. According to the simultaneous determinated law of doublccomponcnt spcctropholomctry, a formula is obtained for Fc(Ⅱ) and Fc(Ⅲ) determination in the same solution at 390.5 nm and 510 nm.Beer's Law was obeyed over the range of 0 to 15 ppm for Fc(Ⅱ )and 0 to 25 ppm for Fc(Ⅲ).Thc determinated errors of standard mixtures arc respectively less than 3.5% for Fc(Ⅱ ) 1.6% for Fc(Ⅲ ) Amounts of Fc(Ⅱ) and Fc(Ⅲ) in paddy soil were determined.Recovery rales were 90.6 to 98.3% for Fc(Ⅱ ) and 97.4 to 102% for Fc(Ⅲ). Also, interference experiments for ions were conducted.